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<h1><a name="title" id="title"></a>Web Services Metadata Exchange (WS-MetadataExchange)</h1>
<h2><a name="w3c-doctype" id="w3c-doctype"></a>W3C Recommendation 13 December 2011</h2><dl><dt>This version:</dt><dd>
   <a href="http://www.w3.org/TR/2011/REC-ws-metadata-exchange-20111213">http://www.w3.org/TR/2011/REC-ws-metadata-exchange-20111213
   </a>
  </dd><dt>Latest version:</dt><dd>
    <a href="http://www.w3.org/TR/ws-metadata-exchange">http://www.w3.org/TR/ws-metadata-exchange
   </a>
  </dd><dt>Previous version:</dt><dd>
   <a href="http://www.w3.org/TR/2011/PR-ws-metadata-exchange-20110927">http://www.w3.org/TR/2011/PR-ws-metadata-exchange-20110927
   </a>
  </dd><dt>Editors:</dt><dd>Doug Davis, IBM</dd><dd>Ashok Malhotra, Oracle</dd><dd>Katy Warr, IBM</dd><dd>Wu Chou, Avaya</dd></dl><p>Please refer to the <a href="http://www.w3.org/2002/ws/ra/errata/ws-metadata-exchange-20111213-errata"><strong>errata</strong></a> for this document, which may
      include normative corrections.</p><p>See also <a href="http://www.w3.org/2003/03/Translations/byTechnology?technology=ws-metadata-exchange"><strong>translations</strong></a>.</p><p class="copyright"><a href="http://www.w3.org/Consortium/Legal/ipr-notice#Copyright">Copyright</a> &copy; 2011 <a href="http://www.w3.org/"><acronym title="World Wide Web Consortium">W3C</acronym></a><sup>&reg;</sup> (<a href="http://www.csail.mit.edu/"><acronym title="Massachusetts Institute of Technology">MIT</acronym></a>, <a href="http://www.ercim.org/"><acronym title="European Research Consortium for Informatics and Mathematics">ERCIM</acronym></a>, <a href="http://www.keio.ac.jp/">Keio</a>), All Rights Reserved. W3C <a href="http://www.w3.org/Consortium/Legal/ipr-notice#Legal_Disclaimer">liability</a>, <a href="http://www.w3.org/Consortium/Legal/ipr-notice#W3C_Trademarks">trademark</a> and <a href="http://www.w3.org/Consortium/Legal/copyright-documents">document use</a> rules apply.</p></div><hr /><div>
<h2><a name="abstract" id="abstract"></a>Abstract</h2><p>
    This specification defines how metadata
    associated with a Web service endpoint can be represented as
    <a href="#WS-Transfer">[WS-Transfer]</a> resources or HTTP resources, how metadata can
    be embedded in <a href="#AddrCore">[WS-Addressing]</a>
    endpoint references, how metadata could be
    retrieved from a metadata resource, and how metadata associated with
    implicit features can be advertised.
   </p></div><div>
<h2><a name="status" id="status"></a>Status of this Document</h2><p><em>
	    This section describes the status of this document at the time
	    of its publication. Other documents may supersede this document.
	    A list of current W3C publications and the latest revision of
	    this technical report can be found in the
	    <a href="http://www.w3.org/TR/">W3C technical reports index</a>
	    at http://www.w3.org/TR/.
	  </em></p><p>
	  This is the 13 December 2011 Recommendation of the <em>Web Services Metadata Exchange (WS-MetadataExchange)</em> specification.
          It has been produced by the
          <a href="http://www.w3.org/2002/ws/ra/">Web
          Services Resource Access Working Group</a> (WG), which is part of the
          <a href="http://www.w3.org/2002/ws/Activity">W3C Web Services
          Activity</a>.
        </p><p>
          The public is encouraged to send comments to the Working Group's public mailing list
          <a href="mailto:public-ws-resource-access-comments@w3.org">
          public-ws-resource-access-comments@w3.org</a>
          mailing list (<a href="http://lists.w3.org/Archives/Public/public-ws-resource-access-comments/">public
          archive</a>). See <a href="http://www.w3.org/Mail/">W3C mailing list and archive usage guidelines</a>.
        </p><p>No changes were made as a result of the Proposed Recommendation phase (see also the <a href="http://www.w3.org/2002/ws/ra/test/scenario.html">test scenario</a> and the <a href="http://www.w3.org/2002/ws/ra/test/testResults.html">implementation report</a>).</p><p>This document has been reviewed by W3C Members, by software developers, and by other W3C groups and interested parties, and is endorsed by the Director as a W3C Recommendation. It is a stable document and may be used as reference material or cited from another document. W3C's role in making the Recommendation is to draw attention to the specification and to promote its widespread deployment. This enhances the functionality and interoperability of the Web.</p><p>
	  This document was produced by a group operating under the
	  <a href="http://www.w3.org/Consortium/Patent-Policy-20040205/">5
	  February 2004 W3C Patent Policy</a>. W3C maintains a
	  <a rel="disclosure" href="http://www.w3.org/2004/01/pp-impl/43088/status">public
	  list of any patent disclosures</a> made in connection with the
	  deliverables of the group; that page also includes instructions for
	  disclosing a patent. An individual who has actual knowledge of a
	  patent which the individual believes contains
	  <a href="http://www.w3.org/Consortium/Patent-Policy-20040205/#def-essential">Essential
	  Claim(s)</a> must disclose the information in accordance with
	  <a href="http://www.w3.org/Consortium/Patent-Policy-20040205/#sec-Disclosure">section
	  6 of the W3C Patent Policy</a>.
	</p></div><div class="toc">
<h2><a name="contents" id="contents"></a>Table of Contents</h2><p class="toc">1 <a href="#composable">Composable Architecture</a><br />
2 <a href="#intro">Introduction</a><br />
&nbsp;&nbsp;&nbsp;2.1 <a href="#Requirements">Requirements</a><br />
&nbsp;&nbsp;&nbsp;2.2 <a href="#Examples">Examples</a><br />
3 <a href="#notterms">Notations and Terminology</a><br />
&nbsp;&nbsp;&nbsp;3.1 <a href="#Conventions">Notational Conventions</a><br />
&nbsp;&nbsp;&nbsp;3.2 <a href="#extensions">Considerations on the Use of Extensibility Points</a><br />
&nbsp;&nbsp;&nbsp;3.3 <a href="#terms">Terminology</a><br />
&nbsp;&nbsp;&nbsp;3.4 <a href="#Compliance">Compliance</a><br />
&nbsp;&nbsp;&nbsp;3.5 <a href="#namespaces">XML Namespaces</a><br />
4 <a href="#web-services-metadata">Web Services Metadata Collection</a><br />
5 <a href="#metadata-resources">Metadata Resources</a><br />
6 <a href="#Retrieving-Metadata">Retrieving Metadata about Service Endpoints</a><br />
&nbsp;&nbsp;&nbsp;6.1 <a href="#GetWSDL">GetWSDL</a><br />
&nbsp;&nbsp;&nbsp;6.2 <a href="#GetMetadata">GetMetadata</a><br />
&nbsp;&nbsp;&nbsp;6.3 <a href="#PutMetadata">PutMetadata</a><br />
&nbsp;&nbsp;&nbsp;6.4 <a href="#DeleteMetadata">DeleteMetadata</a><br />
7 <a href="#MetadataReferences">Metadata References</a><br />
&nbsp;&nbsp;&nbsp;7.1 <a href="#mexLocation">mex:Location</a><br />
&nbsp;&nbsp;&nbsp;7.2 <a href="#mexReference">mex:Reference</a><br />
&nbsp;&nbsp;&nbsp;7.3 <a href="#idp1568496">Examples</a><br />
8 <a href="#Metadata-in-Endpoint-References">Metadata in Endpoint References</a><br />
&nbsp;&nbsp;&nbsp;8.1 <a href="#EPRwithMEX">Endpoint References Containing Metadata</a><br />
&nbsp;&nbsp;&nbsp;8.2 <a href="#WSPAEPR">Associating Policies with Endpoint References</a><br />
9 <a href="#ImplicitWSDL">Exposing Metadata for Implicitly Defined Features</a><br />
10 <a href="#Faults">Faults</a><br />
&nbsp;&nbsp;&nbsp;10.1 <a href="#UnsupportedMetadata">UnsupportedMetadata</a><br />
&nbsp;&nbsp;&nbsp;10.2 <a href="#InvalidMetadata">InvalidMetadata</a><br />
11 <a href="#Security">Security Considerations</a><br />
&nbsp;&nbsp;&nbsp;11.1 <a href="#idp1702016">Metadata and Security Bootstrapping</a><br />
12 <a href="#metadata">WS-MetadataExchange Metadata</a><br />
&nbsp;&nbsp;&nbsp;12.1 <a href="#idp1708960">MetadataExchange Assertion</a><br />
13 <a href="#bootstrapping">Bootstrapping Metadata Retrieval</a><br />
14 <a href="#acks">Acknowledgements</a><br />
15 <a href="#References">References</a><br />
&nbsp;&nbsp;&nbsp;15.1 <a href="#idp1780096">Normative References</a><br />
</p>
<h3><a name="appendices" id="appendices"></a>Appendices</h3><p class="toc">A <a href="#Appendix-A">XML Schema</a><br />
B <a href="#Appendix-B">WSDL</a><br />
C <a href="#changelog">Change Log</a><br />
</p></div><hr /><div class="body"><div class="div1">
<h2><a name="composable" id="composable"></a>1 Composable Architecture</h2><p>
    By using the XML, SOAP <a href="#SOAP11">[SOAP11]</a>,
    <a href="#SOAP12">[SOAP12]</a>, and WSDL <a href="#WSDL11">[WSDL11]</a>
    extensibility models, the Web service
    specifications (WS-*) are designed to be composed with each other
    to provide a rich set of tools for the Web
    services environment. This specification specifically relies on
    other Web service specifications to provide secure, reliable,
    and/or transacted message delivery and to express Web service and
    client policy.
   </p></div><div class="div1">
<h2><a name="intro" id="intro"></a>2 Introduction</h2><p>
    Web services use metadata to describe what other endpoints need to know
    to interact with them. Specifically, <a href="#wspolicy">[WS-Policy]</a>
    describes the capabilities, requirements, and general characteristics
    of Web services; <a href="#WSDL11">[WSDL11]</a> describes abstract message
    operations, concrete network protocols, and endpoint addresses used
    by Web services; XML Schema <a href="#XMLSchema1">[XMLSchema - Part 1]</a>,
    <a href="#XMLSchema2">[XMLSchema - Part 2]</a> describes the structure and contents of
    XML-based messages received by and sent by Web services.
   </p><p>
    To bootstrap communication with Web services this specification defines
    how metadata can be treated as a HTTP resources or as
    <a href="#WS-Transfer">[WS-Transfer]</a> resources
    for retrieval purposes, how metadata can be embedded in WS-Addressing
    endpoint references, and how Web service endpoints can OPTIONALLY
    support a request-response interaction for the retrieval of metadata.
    When the type of metadata sought is clearly known, e.g.,
    <a href="#wspolicy">[WS-Policy]</a>, a requester MAY indicate that only that
    type is to be returned; where additional types of metadata are being
    used, or are expected, or when a requester needs to retrieve all of
    the metadata relevant to subsequent interactions with an endpoint, a
    requester MAY indicate that all available metadata, regardless of their
    types, are expected.
   </p><p>
    The mechanisms defined herein are intended for the retrieval of
    metadata (i.e., Web service description information) only. They are
    not intended to provide a general purpose query or retrieval
    mechanism for other types of data associated with a Web service,
    such as state data, properties and attribute values, etc.
   </p><div class="div2">
<h3><a name="Requirements" id="Requirements"></a>2.1 Requirements</h3><p>
     This specification intends to meet the following requirements:
    </p><ul><li><p>
       Define a mechanism for retrieving metadata about a Web service endpoint.
      </p></li><li><p>
       Define an encapsulation format for metadata.
      </p></li><li><p>
       Treat the metadata about a Web service endpoint as
       <a href="#WS-Transfer">[WS-Transfer]</a> resources, or as an HTTP reachable resource.
      </p></li><li><p>
       Define a bootstrap mechanism for retrieving metadata.
      </p></li><li><p>
       Support future versions of known metadata formats.
      </p></li><li><p>
       Allow new metadata formats to be added.
      </p></li></ul></div><div class="div2">
<h3><a name="Examples" id="Examples"></a>2.2 Examples</h3><p>
     <a href="#GetWSDLRequest">Example 2-1</a> illustrates a sample GetWSDL request
     for the WSDL metadata document of a service.
    </p><div class="exampleOuter">
<div class="exampleHeader"><a name="GetWSDLRequest" id="GetWSDLRequest"></a>Example 2-1: Sample GetWSDL request message</div><div class="exampleInner"><pre>(01)  &lt;s11:Envelope
(02)     xmlns:s11='http://schemas.xmlsoap.org/soap/envelope/'
(03)     xmlns:wsa='http://www.w3.org/2005/08/addressing'&gt;
(04)     xmlns:wst='http://www.w3.org/2011/03/ws-tra'&gt;
(05)    &lt;s11:Header&gt;
(06)      &lt;wsa:Action&gt;
(07)        http://www.w3.org/2011/03/ws-mex/GetWSDL
(08)      &lt;/wsa:Action&gt;
(09)      &lt;wsa:To&gt;http://services.example.org/stockquote&lt;/wsa:To&gt;
(10)      &lt;wsa:ReplyTo&gt;
(11)        &lt;wsa:Address&gt;http://client.example.org&lt;/wsa:Address&gt;
(12)      &lt;/wsa:ReplyTo&gt;
(13)      &lt;wsa:MessageID&gt;
(14)        urn:uuid:1cec121a-82fe-41da-87e1-3b23f254f128
(15)      &lt;/wsa:MessageID&gt;
(16)    &lt;/s11:Header&gt;
(17)    &lt;s11:Body&gt;
(18)      &lt;mex:GetWSDL/&gt;
(19)    &lt;/s11:Body&gt;
(20)  &lt;/s11:Envelope&gt; </pre></div></div><p>
     <a href="#GetWSDLResponse">Example 2-2</a> lists a sample response to the request
     in <a href="#GetWSDLRequest">Example 2-1</a>.
    </p><div class="exampleOuter">
<div class="exampleHeader"><a name="GetWSDLResponse" id="GetWSDLResponse"></a>Example 2-2: Sample GetWSDLResponse message</div><div class="exampleInner"><pre>(01)   &lt;s11:Envelope
(02)      xmlns:s11='http://schemas.xmlsoap.org/soap/envelope/'
(03)      xmlns:wsa='http://www.w3.org/2005/08/addressing'
(04)      xmlns:wsp='http://www.w3.org/ns/ws-policy'
(05)      xmlns:mex='http://www.w3.org/2011/03/ws-mex'&gt;
(06)    &lt;s11:Header&gt;
(07)      &lt;wsa:To&gt;http://client.example.org&lt;/wsa:To&gt;
(08)      &lt;wsa:Action&gt;
(09)        http://www.w3.org/2011/03/ws-mex/GetWSDLResponse
(10)      &lt;/wsa:Action&gt;
(11)      &lt;wsa:RelatesTo&gt;
(12)        urn:uuid:73d7edfc-5c3c-49b9-ba46-2480caee43e9
(13)      &lt;/wsa:RelatesTo&gt;
(14)    &lt;/s11:Header&gt;
(15)    &lt;s11:Body&gt;
(16)      &lt;mex:GetWSDLResponse&gt;
(17)        &lt;wsdl:definitions ...&gt;
(18)          &lt;!-- WSDL data removed for brevity --&gt;
(19)        &lt;/wsdl:definitions&gt;
(18)      &lt;/mex:GetWSDLResponse&gt;
(19)    &lt;/s11:Body&gt;
(20)  &lt;/s11:Envelope&gt; </pre></div></div><p>
     Lines 17-19 in <a href="#GetWSDLResponse">Example 2-2</a> is the WSDL of
     the service.
    </p><p>
     <a href="#GetRequest">Example 2-3</a> illustrates a sample
     <a href="#WS-Transfer">[WS-Transfer]</a> Get request for a resource'
     s representation.
    </p><div class="exampleOuter">
<div class="exampleHeader"><a name="GetRequest" id="GetRequest"></a>Example 2-3: Sample Get request message</div><div class="exampleInner"><pre>(01)  &lt;s11:Envelope
(02)     xmlns:s11='http://schemas.xmlsoap.org/soap/envelope/'
(03)     xmlns:wsa='http://www.w3.org/2005/08/addressing'&gt;
(04)     xmlns:wst='http://www.w3.org/2011/03/ws-tra'&gt;
(05)    &lt;s11:Header&gt;
(06)      &lt;wsa:Action&gt;
(07)        http://www.w3.org/2011/03/ws-tra/Get
(08)      &lt;/wsa:Action&gt;
(09)      &lt;wsa:To&gt;http://services.example.org/stockquote/metadata&lt;/wsa:To&gt;
(10)      &lt;wsa:ReplyTo&gt;
(11)        &lt;wsa:Address&gt;http://client.example.org&lt;/wsa:Address&gt;
(12)      &lt;/wsa:ReplyTo&gt;
(13)      &lt;wsa:MessageID&gt;
(14)        urn:uuid:1cec121a-82fe-41da-87e1-3b23f254f128
(15)      &lt;/wsa:MessageID&gt;
(16)    &lt;/s11:Header&gt;
(17)    &lt;s11:Body&gt;
(18)      &lt;wst:Get/&gt;
(19)    &lt;/s11:Body&gt;
(20)  &lt;/s11:Envelope&gt;</pre></div></div><p>
     The sample request message of <a href="#GetRequest">Example 2-3</a> is a
     <a href="#WS-Transfer">[WS-Transfer]</a> request for the retrieval of a
     resource's representation. In this case, the requested representation
     is the WS-MetadataExchange Metadata element about a Web service
     endpoint. The fact that the resource's representation is a
     mex:Metadata element might be known to the requestor but is not
     explicitly encoded in the request message.
    </p><p>
     <a href="#GetResponse">Example 2-4</a> illustrates a sample response to the
     request of <a href="#GetRequest">Example 2-3</a>.
    </p><div class="exampleOuter">
<div class="exampleHeader"><a name="GetResponse" id="GetResponse"></a>Example 2-4: Sample response message with metadata</div><div class="exampleInner"><pre>(01)  &lt;s11:Envelope
(02)      xmlns:s11='http://schemas.xmlsoap.org/soap/envelope/'
(03)      xmlns:xs='http://www.w3.org/2001/XMLSchema'
(04)      xmlns:wsa='http://www.w3.org/2005/08/addressing'
(05)      xmlns:mex='http://www.w3.org/2011/03/ws-mex'
(06)      xmlns:wsp='http://www.w3.org/ns/ws-policy'
(07)      xmlns:wst='http://www.w3.org/2011/03/ws-tra'
(08)      xmlns:wsdl='http://schemas.xmlsoap.org/wsdl/'&gt;
(09)    &lt;s11:Header&gt;
(10)      &lt;wsa:Action&gt;
(11)        http://www.w3.org/2011/03/ws-tra/GetResponse
(12)      &lt;/wsa:Action&gt;
(13)      &lt;wsa:To&gt;http://client.example.org&lt;/wsa:To&gt;
(14)      &lt;wsa:RelatesTo&gt;
(15)        urn:uuid:1cec121a-82fe-41da-87e1-3b23f254f128
(16)      &lt;/wsa:RelatesTo&gt;
(17)    &lt;/s11:Header&gt;
(18)    &lt;s11:Body&gt;
(19)      &lt;wst:GetResponse&gt;
(20)        &lt;mex:Metadata&gt;
(21)          &lt;mex:MetadataSection Dialect='wsdl:definitions'&gt;
(22)            &lt;wsdl:definitions&gt;
(23)              &lt;!-- WSDL data removed for brevity --&gt;
(24)            &lt;/wsdl:definitions&gt;
(25)          &lt;/mex:MetadataSection&gt;
(26)          &lt;mex:MetadataSection
(27)              Dialect='xs:schema'
(28)              Identifier='http://services.example.org/stockquote/schemas'&gt;
(29)            &lt;mex:MetadataLocation&gt;
(30)              http://services.example.org/stockquote/schemas
(31)            &lt;/mex:MetadataLocation&gt;
(32)          &lt;/mex:MetadataSection&gt;
(33)          &lt;mex:MetadataSection
(34)              Dialect='wsp:Policy'
(35)              Identifier='http://services.example.org/stockquote/policy'&gt;
(36)            &lt;mex:MetadataReference&gt;
(37)              &lt;wsa:Address&gt;
(38)                http://services.example.org/stockquote/policy
(39)              &lt;/wsa:Address&gt;
(40)            &lt;/mex:MetadataReference&gt;
(41)          &lt;/mex:MetadataSection&gt;
(42)        &lt;/mex:Metadata&gt;
(43)      &lt;/wst:GetResponse&gt;
(44)    &lt;/s11:Body&gt;
(45)  &lt;/s11:Envelope&gt;</pre></div></div><p>
     The message of <a href="#GetResponse">Example 2-4</a> is a
     <a href="#WS-Transfer">[WS-Transfer]</a>
     response message to the request of <a href="#GetRequest">Example 2-3</a>. The
     content
     of the <b>[Body]</b> (lines 18-44) is a mex:Metadata element with
     metadata
     about the Web service endpoint (lines 20-42). The mex:Metadata
     contains three MetadataSections. The first MetadataSection
     (lines 21-25) contains the <a href="#WSDL11">[WSDL11]</a> of the Web
     service endpoint. The second MetadataSection (lines 26-32) contains
     the location of the XML Schemas <a href="#XMLSchema1">[XMLSchema - Part 1]</a>,
     <a href="#XMLSchema2">[XMLSchema - Part 2]</a> used by the WSDL document. The schemas can
     be retrieved through an HTTP GET request at the identified URL
     (lines 29-31). The third MetadataSection (lines 33-41) contains
     the <a href="#AddrCore">[WS-Addressing]</a> endpoint reference (lines 36-40) of
     a <a href="#WS-Transfer">[WS-Transfer]</a> resource the representation of
     which is a <a href="#wspolicy">[WS-Policy]</a> document as indicated by
     the Dialect attribute (line 34).
    </p><p>
     While the WS-Policy of the Web service endpoint could be retrieved using
     a WS-Transfer Get request directed to the endpoint identified by the
     mex:MetadataReference element in lines 36-40 of
     <a href="#GetResponse">Example 2-4</a>,
     some endpoints MAY support explicit requests for metadata via the
     GetMetadata operation.
     <a href="#GetMexReq">Example 2-5</a> illustrates a sample GetMetadata request
     for the <a href="#wspolicy">[WS-Policy]</a>.
    </p><div class="exampleOuter">
<div class="exampleHeader"><a name="GetMexReq" id="GetMexReq"></a>Example 2-5: Sample GetMetadata request message</div><div class="exampleInner"><pre>(01)  &lt;s11:Envelope
(02)      xmlns:s11='http://schemas.xmlsoap.org/soap/envelope/'
(03)      xmlns:wsa='http://www.w3.org/2005/08/addressing'
(04)      xmlns:wsp='http://www.w3.org/ns/ws-policy'
(05)      xmlns:mex='http://www.w3.org/2011/03/ws-mex' &gt;
(06)    &lt;s11:Header&gt;
(07)      &lt;wsa:To&gt;http://services.example.org/stockquote&lt;/wsa:To&gt;
(08)      &lt;wsa:Action&gt;
(09)        http://www.w3.org/2011/03/ws-mex/GetMetadata
(10)      &lt;/wsa:Action&gt;
(11)      &lt;wsa:MessageID&gt;
(12)        urn:uuid:73d7edfc-5c3c-49b9-ba46-2480caee43e9
(13)      &lt;/wsa:MessageID&gt;
(14)      &lt;wsa:ReplyTo&gt;
(15)        &lt;wsa:Address&gt;http://client.example.org&lt;/wsa:Address&gt;
(16)      &lt;/wsa:ReplyTo&gt;
(17)    &lt;/s11:Header&gt;
(18)    &lt;s11:Body&gt;
(19)      &lt;mex:GetMetadata&gt;
(20)        &lt;mex:Dialect Type='{http://www.w3.org/ns/ws-policy}Policy'
(21)          Identifier='http://services.example.org/stockquote/policy'/&gt;
(22)      &lt;/mex:GetMetadata&gt;
(23)    &lt;/s11:Body&gt;
(24)  &lt;/s11:Envelope&gt;</pre></div></div><p>
     Lines 8-10 in <a href="#GetMexReq">Example 2-5</a> indicate this is a GetMetadata
     request. As lines 19-22 indicate, this request is for the policy of
     the Web service endpoint (line 7).
    </p><p>
     <a href="#GetMexRes">Example 2-6</a> lists a sample response to the request in
     <a href="#GetMexReq">Example 2-5</a>.
    </p><div class="exampleOuter">
<div class="exampleHeader"><a name="GetMexRes" id="GetMexRes"></a>Example 2-6: Sample GetMetadataResponse message</div><div class="exampleInner"><pre>(01)   &lt;s11:Envelope
(02)      xmlns:s11='http://schemas.xmlsoap.org/soap/envelope/'
(03)      xmlns:wsa='http://www.w3.org/2005/08/addressing'
(04)      xmlns:wsp='http://www.w3.org/ns/ws-policy'
(05)      xmlns:mex='http://www.w3.org/2011/03/ws-mex'&gt;
(06)    &lt;s11:Header&gt;
(07)      &lt;wsa:To&gt;http://client.example.org&lt;/wsa:To&gt;
(08)      &lt;wsa:Action&gt;
(09)        http://www.w3.org/2011/03/ws-mex/GetMetadataResponse
(10)      &lt;/wsa:Action&gt;
(11)      &lt;wsa:RelatesTo&gt;
(12)        urn:uuid:73d7edfc-5c3c-49b9-ba46-2480caee43e9
(13)      &lt;/wsa:RelatesTo&gt;
(14)    &lt;/s11:Header&gt;
(15)    &lt;s11:Body&gt;
(16)      &lt;mex:GetMetadataResponse&gt;
(17)        &lt;mex:Metadata&gt;
(18)          &lt;mex:MetadataSection
(19)              Dialect='wsp:Policy'
(20)              Identifier='http://services.example.org/stockquote/policy'&gt;
(21)            &lt;wsp:Policy&gt;
(22)              &lt;wsp:ExactlyOne&gt;
(23)                &lt;!-- Policy alternatives --&gt;
(24)              &lt;/wsp:ExactlyOne&gt;
(25)            &lt;/wsp:Policy&gt;
(26)          &lt;/mex:MetadataSection&gt;
(27)        &lt;/mex:Metadata&gt;
(28)      &lt;/mex:GetMetadataResponse&gt;
(29)    &lt;/s11:Body&gt;
(30)  &lt;/s11:Envelope&gt;</pre></div></div><p>
     Lines 8-10 in <a href="#GetMexRes">Example 2-6</a> indicate this message is a
     response to a GetMetadata request, and lines 11-13 indicate that it
     is a response to the request in <a href="#GetMexReq">Example 2-5</a>. Lines
     17-26 contain a single MetadataSection (lines 18-26); line 19
     indicates that the metadata in this section is of type, or
     Dialect, WS-Policy while line 20 identifies a specific policy
     document. Line 23 would have contained the policy expressions for the
     Web service endpoint to which the GetMetadata request of
     <a href="#GetMexReq">Example 2-5</a> was directed.
    </p></div></div><div class="div1">
<h2><a name="notterms" id="notterms"></a>3 Notations and Terminology</h2><p>
     This section specifies the notations, namespaces, and
     terminology used in this specification.
   </p><div class="div2">
<h3><a name="Conventions" id="Conventions"></a>3.1 Notational Conventions</h3><p>
     The keywords "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
     "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
     document are to be interpreted as described in RFC 2119
     <a href="#RFC2119">[RFC 2119]</a>.
    </p><p>
     This specification uses the following syntax to define outlines for
     messages:
    </p><ul><li><p>
       The syntax appears as an XML instance, but values in italics
       indicate data types instead of literal values.
      </p></li><li><p>
       Characters are appended to elements and attributes to indicate
       cardinality:
      </p><ul><li><p> "?" (0 or 1) </p></li><li><p> "*" (0 or more) </p></li><li><p> "+" (1 or more) </p></li></ul></li><li><p>
       The character "|" is used to indicate a choice between alternatives.
      </p></li><li><p>
       The characters "(" and ")" are used to indicate that contained items
       are to be treated as a group with respect to cardinality or choice.
      </p></li><li><p>
       The characters "[" and "]" are used to call out references and
       property names.
      </p></li><li><p>
       Ellipses (i.e., "...") indicate points of extensibility.
      </p></li><li><p>
       XML namespace prefixes (see <a href="#XMLNS">Table 3-1</a>) are used to
       indicate the namespace of the element being defined.
      </p></li></ul><p>
     In addition to Message Information Header properties
     <a href="#AddrCore">[WS-Addressing]</a>,
     this specification uses the following properties to define messages:
    </p><dl><dt class="label"> <b>[Headers]</b> </dt><dd><p> Unordered message headers. </p></dd><dt class="label"> <b>[Action]</b> </dt><dd><p> The value to be used for the wsa:Action IRI. </p></dd><dt class="label"> <b>[Body]</b> </dt><dd><p> A message body. </p></dd></dl><p>
     These properties bind to a SOAP Envelope as follows:
    </p><div class="exampleOuter"><div class="exampleInner"><pre>&lt;s:Envelope&gt;
  &lt;s:Header&gt;
    <b>[Headers]</b>
    &lt;wsa:Action&gt;<b>[Action]</b>&lt;/wsa:Action&gt;
    ...
  &lt;/s:Header&gt;
  &lt;s:Body&gt;<b>[Body]</b>&lt;/s:Body&gt;
&lt;/s:Envelope&gt;</pre></div></div><p>
     This specification can be used in terms of XML Information Set (Infoset)
     <a href="#XMLInfoset">[XML Infoset]</a>, even though the specification uses XML 1.0
     terminology. Valid Infoset for this specification is the one
     serializable in XML 1.0, hence the use of XML 1.0.
    </p><p>
     The term "generate" is used in relation to the various faults defined
     by this specification to imply that a fault is produced and no
     further processing SHOULD be performed. In these cases the fault
     SHOULD be transmitted. However, there might be reasons when a compliant
     implementation can choose not to transmit the fault - for example,
     security concerns - in these situations the service MAY choose
     not to transmit the fault.
    </p></div><div class="div2">
<h3><a name="extensions" id="extensions"></a>3.2 Considerations on the Use of Extensibility Points</h3><p>
     The elements defined in this specification MAY be extended at the
     points indicated by their outlines and schema. Implementations MAY
     add child elements and/or attributes at the indicated extension
     points but MUST NOT contradict the semantics of the parent and/or
     owner, respectively. If a receiver does not recognize an extension,
     the receiver SHOULD ignore that extension. Senders MAY indicate
     the presence of an extension that has to be understood through the use
     of a corresponding SOAP Header with a soap:mustUnderstand attribute
     with the value "1".
    </p><p>
     In cases where it is either desirable or necessary for the receiver
     of a request that has been extended to indicate that it has
     recognized and accepted the semantics associated with that extension,
     it is RECOMMENDED that the receiver add a corresponding extension
     to the response message.  The definition of an extension SHOULD clearly
     specify how the extension that appears in the response correlates
     with that in the corresponding request.
    </p><p>
     Extension elements and attributes MUST NOT use the Web Services
     Metadata Exchange namespace URI.
    </p></div><div class="div2">
<h3><a name="terms" id="terms"></a>3.3 Terminology</h3><dl><dt class="label"> Service Endpoint </dt><dd><p>
        A Web service that is addressable using a WS-Addressing endpoint
        reference. Within the context of this specification, it is assumed
        that the consumer's primary goal is to interact with this service.
       </p></dd><dt class="label"> Metadata Resource </dt><dd><p>
        A specialized Web service that is addressable using either a
        WS-Addressing endpoint reference or a URL and whose main purpose is
        to expose the XML representation of a piece of metadata associated
        with a Service Endpoint.
       </p></dd></dl><p>
     While technically a single Web service can be both a 'Service Endpoint'
     as well as a 'Metadata Resource', for the purposes of clarifying the
     various expectations of these two types Web services, this specification
     will discuss these two concepts (or roles) as distinct entities.
    </p></div><div class="div2">
<h3><a name="Compliance" id="Compliance"></a>3.4 Compliance</h3><p>
     An implementation is not compliant with this specification if it fails to
     satisfy one or more of the MUST or REQUIRED level requirements defined
     herein.  A SOAP Node MUST NOT use the XML namespace identifier for this
     specification (listed in <a href="#namespaces"><b>3.5 XML Namespaces</b></a>) within SOAP
     Envelopes unless it is compliant with this specification.
    </p><p>
     Normative text within this specification takes precedence over the XML
     Schema and WSDL descriptions, which in turn take precedence over outlines,
     which in turn take precedence over examples.
    </p><p>
     All messages defined by this specification MUST conform to the
     WS-Addressing specifications and be sent to a Web service that
     is addressable by an EPR (see <a href="#AddrCore">[WS-Addressing]</a>).
    </p><p>
     Unless otherwise noted, all IRIs are absolute IRIs and IRI comparison
     MUST be performed according to <a href="#RFC3987">[RFC 3987]</a> section 5.3.1.
    </p><p>
     For any message defined by this specification, any OPTIONAL elements
     or attributes in the message MAY be used by senders of the message;
     however receivers of those messages MUST support those OPTIONAL
     elements and attributes, unless other behavior is explicitly defined
     by this specification.
    </p><p>
     Support for the GetMetadata operation by a Web service is
     OPTIONAL. If metadata about a Web service endpoint is referenced by
     a MetadataReference, which is a
     <a href="#AddrCore">[WS-Addressing]</a> endpoint reference, then the MetadataReference
     MUST refer to a <a href="#WS-Transfer">[WS-Transfer]</a> resource.
     The referred resource MAY also support other resource management
     and access specifications (e.g. HTTP, WS-ResourceFramework).
    </p><p>
     Implementations are expected to support both UTF-8 and UTF-16 as
     described in XML 1.0.
    </p><p>
     Implementations of this specification MUST conform to the corrected
     version of WSDL as defined by the 'WSDL Correction' sections of WS-I
     Basic Profile 1.2 <a href="#BP12">[BP12]</a> and WS-I Basic Profile 2.0
     <a href="#BP20">[BP20]</a>.
    </p></div><div class="div2">
<h3><a name="namespaces" id="namespaces"></a>3.5 XML Namespaces</h3><p>
     The XML namespace URI that MUST be used by implementations of this
     specification is:
    </p><div class="exampleOuter"><div class="exampleInner"><pre><a href="http://www.w3.org/2011/03/ws-mex">http://www.w3.org/2011/03/ws-mex</a></pre></div></div><p>
     <a href="#XMLNS">Table 3-1</a> lists XML namespaces that are used in this
     specification. The choice of any namespace prefix is arbitrary and
     not semantically significant.
    </p><a name="XMLNS" id="XMLNS"></a><table border="1"><caption>Table 3-1:  Prefixes and XML namespaces used in this specification </caption><tbody><tr><th align="left"> Prefix </th><th align="left"> XML Namespaces </th><th align="left"> Specification(s) </th></tr><tr><td> s </td><td> (Either SOAP 1.1 or 1.2) </td><td> (Either SOAP 1.1 or 1.2) </td></tr><tr><td> s11 </td><td> http://schemas.xmlsoap.org/soap/envelope/ </td><td> <a href="#SOAP11">[SOAP11]</a> </td></tr><tr><td> s12 </td><td> http://www.w3.org/2003/05/soap-envelope </td><td> <a href="#SOAP12">[SOAP12]</a> </td></tr><tr><td> wsa </td><td> http://www.w3.org/2005/08/addressing </td><td> <a href="#AddrCore">[WS-Addressing]</a> </td></tr><tr><td> wsdl </td><td> http://schemas.xmlsoap.org/wsdl/ </td><td> <a href="#WSDL11">[WSDL11]</a> </td></tr><tr><td> wsp </td><td> http://www.w3.org/ns/ws-policy </td><td> <a href="#wspolicy">[WS-Policy]</a> </td></tr><tr><td> mex </td><td> http://www.w3.org/2011/03/ws-mex </td><td> This specification </td></tr><tr><td> xs </td><td> http://www.w3.org/2001/XMLSchema </td><td> <a href="#XMLSchema1">[XMLSchema - Part 1]</a> </td></tr><tr><td> wssa </td><td> http://www.w3.org/2011/03/ws-sas </td><td> <a href="#WS-SOAPAssertions">[WS-SOAPAssertions]</a> </td></tr><tr><td> wst </td><td> http://www.w3.org/2011/03/ws-tra </td><td> <a href="#WS-Transfer">[WS-Transfer]</a> </td></tr></tbody></table><p>
     The working group intends to update the value of the Web Services
     Metadata Exchange namespace URI each time a new version of this document
     is published until such time that the document reaches Candidate
     Recommendation status. Once it has reached Candidate Recommendation
     status, the working group intends to maintain the value of the
     Web Services Metadata Exchange namespace URI that was assigned in the
     Candidate Recommendation unless significant changes are made that
     impact the implementation or break post-CR implementations of the
     specification. Also see
     <a href="http://www.w3.org/2001/tag/doc/namespaceState.html">
      http://www.w3.org/2001/tag/doc/namespaceState.html
     </a> and
     <a href="http://www.w3.org/2005/07/13-nsuri">
      http://www.w3.org/2005/07/13-nsuri
     </a>.
    </p></div></div><div class="div1">
<h2><a name="web-services-metadata" id="web-services-metadata"></a>4 Web Services Metadata Collection</h2><p>
    The WS-MetadataExchange Metadata element is a collection of metadata units
    such as <a href="#WSDL11">[WSDL11]</a> definitions, <a href="#XMLSchema1">[XMLSchema - Part 1]</a>
    documents, <a href="#wspolicy">[WS-Policy]</a> expressions, etc. Each unit
    corresponds to metadata for a given scope, domain, or namespace. The
    collection of units is represented by a Metadata element, and units
    within the collection are represented by MetadataSection elements.
   </p><p>
    To facilitate processing, MetadataSections are tagged with a
    @Dialect and @Identifier of the metadata unit. To ensure
    scalability, a unit of metadata MAY be embedded within its
    MetadataSection or MAY be included by reference, either an endpoint
    reference <a href="#AddrCore">[WS-Addressing]</a>
    (MetadataReference) or a URL (MetadataLocation).
   </p><p>
    The outline for the Metadata element is:
   </p><div class="exampleOuter"><div class="exampleInner"><pre>&lt;mex:Metadata ...&gt;
  &lt;mex:MetadataSection Dialect='<em>xs:QName</em>'
                       Identifier='<em>xs:anyURI</em>' ...&gt;
  (
    &lt;mex:MetadataReference ...&gt;
      <em>endpoint-reference-type</em>
    &lt;/mex:MetadataReference&gt;
    |
    &lt;mex:MetadataLocation ...&gt; <em>xs:anyURI</em> &lt;/mex:MetadataLocation&gt;
    |
    DialectSpecificElement
  )
  &lt;/mex:MetadataSection&gt; *
  <em>xs:any</em>*
&lt;/mex:Metadata&gt;</pre></div></div><p>
    The following describes additional constraints on the outline listed
    above:
   </p><dl><dt class="label">/mex:Metadata</dt><dd><p>
       This contains one MetadataSection child for each distinct unit of
       metadata. When there is a large amount of metadata, the children
       SHOULD contain MetadataReferences or MetadataLocations instead of the
       actual information.
      </p></dd><dt class="label">/mex:Metadata/mex:MetadataSection</dt><dd><p>
       This represents a single unit of metadata (e.g., a WSDL
       definitions, an XML Schema document) for a given scope, domain,
       or namespace. A MetadataSection contains exactly one child
       element, either the embedded XML for the metadata unit, an
       endpoint reference to a Metadata Resource for the metadata
       unit, or a URL to metadata unit.
      </p></dd><dt class="label">/mex:Metadata/mex:MetadataSection/@Dialect</dt><dd><p>
       This REQUIRED attribute
       indicates the type and version of the metadata unit
       contained in this MetadataSection (e.g., WSDL version 1.1).
       This MUST be the QName of the root element of the metadata.
      </p><p>
       If there is more than one metadata unit with the same Dialect, e.g.,
       more than one XML Schema document, including them all, one per
       MetadataSection, is explicitly encouraged.
      </p><p>
       Note: the QName is serialized as {namespace-uri}localName.
      </p></dd><dt class="label">
      /mex:Metadata/mex:MetadataSection/@Dialect='{http://www.w3.org/2011/03/ws-mex}Metadata'
     </dt><dd><p>
       This Dialect value indicates that the type of the metadata contained
       within the MetadataSection is itself a mex:Metadata element.
       When the Dialect value is used in conjunction with
       mex:MetadataReference or mex:MetadataLocation, the Dialect value
       provides the ability to include metadata by reference (an endpoint
       reference or a URL).
       <a href="#EPRMD">Example 8-2</a> illustrates the use of this Dialect.
      </p></dd><dt class="label">/mex:Metadata/mex:MetadataSection/@Identifier</dt><dd><p>
       This REQUIRED attribute indicates the Identifier for the metadata unit
       in this MetadataSection. Identifier is an absolute IRI.
      </p><p>
       The interpretation of Identifier is Dialect-specific.
       If the value of the
       Dialect attribute of the MetadataSection is one of the values in
       the table below, the Identifier attribute MUST have the indicated,
       corresponding value. In other cases the value of the Identifier
       attribute is not constrained.
       If there is no algorithm defined for how to determine the Identifier
       value for a particular type of metadata, then the Identifier MUST
       use a value of "" (empty string).
      </p><table border="1"><tbody><tr><th align="left"> Dialect QName </th><th align="left"> @Identifier value </th></tr><tr><td> xs:schema </td><td> xs:schema/@targetNamespace </td></tr><tr><td> wsdl:definitions </td><td> wsdl:definitions/@targetNamespace  </td></tr><tr><td> wsp:Policy </td><td> wsp:Policy/@Name </td></tr><tr><td> mex:Metadata </td><td> "" (empty string) </td></tr></tbody></table><p>
       If there is more than one MetadataSection with the same
       identifier, e.g., more than one XML Schema in the same target
       namespace, including them all, one per MetadataSection, is
       REQUIRED.
      </p></dd><dt class="label">/mex:Metadata/mex:MetadataSection/mex:MetadataReference</dt><dd><p>
       This is an endpoint reference to a metadata resource and is
       of type EndpointReferenceType as defined by <a href="#AddrCore">[WS-Addressing]</a>.
       The metadata resource MUST support the Get operation
       <a href="#WS-Transfer">[WS-Transfer]</a> to allow the retrieval of the
       metadata unit for the MetadataSection's Dialect and Identifier.
       When this element is present, it MUST have no
       element siblings.
      </p></dd><dt class="label">/mex:Metadata/mex:MetadataSection/mex:MetadataLocation</dt><dd><p>
       This contains a URL to metadata, and the metadata MUST be
       retrievable from that URL using the primary access mechanism for
       the scheme of the URL. For example, for an HTTP URL, the
       metadata MUST be retrievable by sending an HTTP GET request to
       the URL. When this element is present, it MUST have no
       element siblings.
      </p></dd><dt class="label">/mex:Metadata/mex:MetadataSection/DialectSpecificElement</dt><dd><p>
       When any element other than MetadataReference or MetadataLocation is
       present, the element is to be interpreted as the representation of
       the metadata unit associated with the MetadataSection's Dialect
       and Identifier.
      </p></dd></dl></div><div class="div1">
<h2><a name="metadata-resources" id="metadata-resources"></a>5 Metadata Resources</h2><p>
    A resource is referred to as a 'metadata resource' when its
    representation is of type mex:Metadata, as defined in
    <a href="#web-services-metadata"><b>4 Web Services Metadata Collection</b></a>, or any other document format
    (e.g. <a href="#XMLSchema1">[XMLSchema - Part 1]</a>,<a href="#XMLSchema2">[XMLSchema - Part 2]</a>,
    <a href="#WSDL11">[WSDL11]</a>, <a href="#wspolicy">[WS-Policy]</a>) that is used to
    describe some aspect of a service.
   </p><p>
    When a metadata resource is addressable by an endpoint reference
    the resource's representation MUST be retrievable using the Get operation
    defined in <a href="#WS-Transfer">[WS-Transfer]</a> and MAY be updated as any other
    <a href="#WS-Transfer">[WS-Transfer]</a> resource.  When the resource is addressed by
    a URL the resource's representation MUST be retrievable using an
    HTTP GET and MAY be updated as any other HTTP resource.
   </p><p>
    To retrieve the representation of a metadata resource, a requester MAY
    send a <a href="#WS-Transfer">[WS-Transfer]</a> Get request message to the metadata
    resource's endpoint reference, or it MAY send an HTTP GET to the metadata
    resource's IRI. These will fetch a one-time snapshot of the metadata.
    The metadata associated with a service endpoint MAY be available as
    multiple metadata resources.
   </p><p>
    The representation of a metadata resource MAY be a mex:Metadata element
    which MAY contain one or more mex:MetadataSection children. Each
    MetadataSection is identified by a specific Dialect and contains
    information whose format and content depend on the Dialect.
   </p><p>
    A Web service endpoint MAY have one or more associated metadata
    resources.
   </p><p>
    It is important to note that metadata resources are themselves services.
    In other words, a metadata resource can still accept GetWSDL or
    GetMetadata requests, but such requests would apply to the metadata
    about the metadata resource and not the original service that the metadata
    resource describes.
   </p></div><div class="div1">
<h2><a name="Retrieving-Metadata" id="Retrieving-Metadata"></a>6 Retrieving Metadata about Service Endpoints</h2><p>
    This specification defines two mechanism by which a requester can ask
    a WS-MetadataExchange compliant 'service endpoint' for its metadata:
    the GetWSDL operation and the GetMetadata
    operation.
   </p><p>
    GetWSDL provides the means to obtain a starting point for constructing
    the relationships between the metadata documents that apply to a
    service. It is useful in situations when the requester has no prior
    knowledge of these relationships. The GetMetadata operation is useful
    in cases where the requester is already aware of these relationships
    or when it wishes to obtain a specific metadata document.
   </p><div class="div2">
<h3><a name="GetWSDL" id="GetWSDL"></a>6.1 GetWSDL</h3><p>
     A requester MAY send a GetWSDL request message to an endpoint to
     retrieve the service's WSDL metadata document. This operation MUST
     be supported by compliant WS-MetadataExchange service endpoints.
     Note, the GetWSDL operation
     is a SOAP-based equivalent feature to the commonly supported HTTP GET
     targeted at an endpoint's URL appended with "?wsdl".
    </p><p>
     Through examination of this WSDL document, and by following any
     references within it, a requester MUST be able to retrieve any metadata
     needed to interact with the service. For example, the schema used by
     the service might be embedded within the WSDL or could be available by
     following a xs:import element. Likewise, as discussed in
     <a href="#ImplicitWSDL"><b>9 Exposing Metadata for Implicitly Defined Features</b></a> through the inclusion of policy
     assertions and nested metadata (or metadata references) within those
     policy assertions, a requester MUST be able to determine the set of
     implicit features available and any related metadata associated with
     those features.
    </p><p>
     The normative outline for a GetWSDL request is:
    </p><div class="exampleOuter"><div class="exampleInner"><pre><b>[Action]</b>
  http://www.w3.org/2011/03/ws-mex/GetWSDL

<b>[Body]</b>
  &lt;mex:GetWSDL ...&gt;
    <em>xs:any</em>*
  &lt;/mex:GetWSDL&gt; </pre></div></div><p>
     If the endpoint accepts a GetWSDL request, it MUST reply with a
     GetWSDLResponse message. The normative outline for a GetWSDLResponse is:
    </p><div class="exampleOuter"><div class="exampleInner"><pre><b>[Action]</b>
  http://www.w3.org/2011/03/ws-mex/GetWSDLResponse

<b>[Body]</b>
  &lt;mex:GetWSDLResponse ...&gt;
    <em>xs:any</em>*
  &lt;/mex:GetWSDLResponse&gt; </pre></div></div><p>
     The following describes additional, normative constraints on the
     outline listed above:
    </p><dl><dt class="label"> <b>[Body]</b>/mex:GetWSDLResponse/xs:any </dt><dd><p>
        When the GetWSDLResponse element contains any child elements, the
        first element MUST either be the WSDL metadata document, or a
        reference to the WSDL metadata document, of the endpoint.
        While an endpoint MAY choose to return a reference to the WSDL, it is
        STRONGLY RECOMMENDED that the WSDL metadata document itself be
        returned.
        If a requester would like a reference to the WSDL then it can use the
        GetMetadata operation specifying the appropriate Content URI.
       </p><p>
        Any extension elements MUST appear after the WSDL document/reference.
        The absence of any child elements indicates that the endpoint does
        not have any WSDL document, or additional metadata, associated with it.
       </p></dd><dt class="label"> <b>[Body]</b>/mex:GetWSDLResponse/wsdl:definitions </dt><dd><p>
        When present this OPTIONAL element contains the WSDL metadata
        document of the endpoint.
       </p></dd><dt class="label"> <b>[Body]</b>/mex:GetWSDLResponse/mex:Location </dt><dd><p>
        When present this OPTIONAL element contains a reference to the
        WSDL metadata document of the endpoint.
       </p></dd><dt class="label"> <b>[Body]</b>/mex:GetWSDLResponse/mex:Reference </dt><dd><p>
        When present this OPTIONAL element contains a reference to the
        WSDL metadata document of the endpoint.
       </p></dd></dl><p>
     This operation is safe; it will not result in any side effect
     imputable to the requester. This means that in case of an underlying
     protocol error that might get unnoticed, resending the same request
     can be done automatically.
    </p></div><div class="div2">
<h3><a name="GetMetadata" id="GetMetadata"></a>6.2 GetMetadata</h3><p>
     A requester MAY send a GetMetadata request message to an endpoint to
     retrieve the metadata associated with that endpoint.
     This operation MAY be supported by WS-MetadataExchange compliant
     service endpoints.
     Observe that, in the case where
     a service endpoint is also a <a href="#WS-Transfer">[WS-Transfer]</a> resource,
     the <a href="#WS-Transfer">[WS-Transfer]</a> Get operation allows requesters to
     retrieve the resource representation associated with that endpoint
     (i.e. the "data"), while the GetMetadata operation can be used to
     retrieve that endpoint's metadata. The normative outline for a
     GetMetadata request is:
    </p><div class="exampleOuter"><div class="exampleInner"><pre><b>[Action]</b>
  http://www.w3.org/2011/03/ws-mex/GetMetadata

<b>[Body]</b>
  &lt;mex:GetMetadata Content='<em>xs:any</em>' ? ...&gt;
    &lt;mex:Dialect Type='<em>mex:QNameSerialization</em>'
                 Identifier='<em>xs:anyURI</em>' ?
                 Content='<em>xs:anyURI</em>' ? .../&gt; *
    <em>xs:any</em>*
  &lt;/mex:GetMetadata&gt; </pre></div></div><p>
     The following describes additional, normative constraints on the
     outline listed above:
    </p><dl><dt class="label"> <b>[Body]</b>/mex:GetMetadata@Content </dt><dd><p>
        This OPTIONAL attribute, when present, specifies the default
        content form IRI for this request.   When this attribute is
        not present, the default content form IRI is
        'http://www.w3.org/2011/03/ws-mex/Content/Any'.
       </p><p>
        If no dialect elements are present in the request, the response
        MUST only include MetadataSections of the content form specified
        by this attribute.
       </p><p>
        If the specified content form is not available, or not known,
        then the response MUST include zero MetadataSections of the
        specified form.
       </p><p>
        This specification defines the following content form IRIs:
       </p><table border="1"><tbody><tr><th align="left"> Content Form IRI </th><th align="left"> Form </th></tr><tr><td> http://www.w3.org/2011/03/ws-mex/Content/EPR </td><td> A MetadataReference element is returned </td></tr><tr><td> http://www.w3.org/2011/03/ws-mex/Content/URI </td><td> A MetadataLocation element is returned </td></tr><tr><td> http://www.w3.org/2011/03/ws-mex/Content/Metadata </td><td> The metadata is embedded </td></tr><tr><td> http://www.w3.org/2011/03/ws-mex/Content/Any </td><td> The service is free to choose any content form </td></tr><tr><td> http://www.w3.org/2011/03/ws-mex/Content/All </td><td> The service MUST return all available content forms </td></tr></tbody></table></dd><dt class="label"> <b>[Body]</b>/mex:GetMetadata/mex:Dialect </dt><dd><p>
        When this repeating OPTIONAL element is present, the response MUST
        include only MetadataSections corresponding to metadata specified by
        the combination of the QName, Identifier and Content attributes of
        each of the Dialect elements. For each Dialect element if there is no
        metadata for that combination of attributes then the response
        MUST NOT include any MetadataSections for that Dialect element.
       </p><p>
        When this element is not present, the endpoint MUST return all
        available metadata.
       </p></dd><dt class="label"> <b>[Body]</b>/mex:GetMetadata/mex:Dialect@Type </dt><dd><p>
        This REQUIRED attribute specifies the Metadata Dialect. The response
        MUST only include MetadataSections corresponding to the Dialect
        specified by this QName. If the receiver does not have any
        MetadataSections of this indicated Dialect, the response MUST
        include zero MetadataSections for this QName.
       </p><p>
        Note: the QName is serialized as {namespace-uri}localName.
       </p></dd><dt class="label"> <b>[Body]</b>/mex:GetMetadata/mex:Dialect@Identifier </dt><dd><p>
        When this OPTIONAL attribute is present, the response MUST include only
        MetadataSections with the indicated identifier; if the receiver
        does not have any MetadataSections of the indicated identifier,
        the response MUST include zero MetadataSections for this
        QName/Identifier pair.
        When this attribute is not present, the implied value is any
        identifier.
        If multiple MetadataSections have the indicated Dialect
        and Identifier then all of them MUST be returned.
        Note that the absence of this attribute is not equivalent to its
        presence with a value of "" - which indicates a request to retrieve
        all metadata whose Identifier is the empty string.
       </p></dd><dt class="label"> <b>[Body]</b>/mex:GetMetadata/mex:Dialect@Content </dt><dd><p>
        For the dialect indicated, the response MUST include only
        MetadataSections of the content form specified by this attribute.
       </p><p>
        When this OPTIONAL attribute is not present, it defaults to the
        value of the [Body]/mex:GetMetadata@Content attribute.
       </p><p>
        If the specified content form is not available, or not known,
        then the response MUST include zero
        MetadataSections of the specified form for this QName/Identifier pair.
       </p></dd></dl><p>
     Subject to authorization restrictions, services MUST return all the
     MetadataSections corresponding to the GetMetadata request.  Note
     that there can be multiple MetadataSections returned for any one
     combination of Dialect, Identifier and Content values.
    </p><p>
     If an endpoint accepts a GetMetadata request, it MUST reply with
     a GetMetadataResponse message. The normative outline for a
     GetMetadataResponse is:
    </p><div class="exampleOuter"><div class="exampleInner"><pre><b>[Action]</b>
  http://www.w3.org/2011/03/ws-mex/GetMetadataResponse

<b>[Body]</b>
  &lt;mex:GetMetadataResponse ...&gt;
    &lt;mex:Metadata ...&gt; ... &lt;/mex:Metadata&gt;
    <em>xs:any</em>*
  &lt;/mex:GetMetadataResponse&gt;</pre></div></div><p>
     The following describes additional, normative constraints on the
     outline listed above:
    </p><dl><dt class="label"> <b>[Body]</b>/mex:GetMetadataResponse/mex:Metadata </dt><dd><p>
        The body of the response message MUST contain one mex:Metadata
        element as defined in <a href="#web-services-metadata"><b>4 Web Services Metadata Collection</b></a>.
       </p><p>
        Note, in cases where the requester, through the use of @Content
        and/or mex:Dialect sub-elements in the GetMetadata request, has
        excluded all the metadata maintained by the service, this
        element will be empty.
       </p></dd></dl><p>
     This operation is safe; it will not result in any side effect
     imputable to the requester. This means that in case of an underlying
     protocol error that might get unnoticed, resending the same request
     can be done automatically.
    </p></div><div class="div2">
<h3><a name="PutMetadata" id="PutMetadata"></a>6.3 PutMetadata</h3><p>
     A requester MAY send a PutMetadata request message to an endpoint to
     update the metadata associated with that endpoint. This operation MAY
     be supported by WS-MetadataExchange compliant service endpoints. Observe
     that, in the case where a service endpoint is also a
     <a href="#WS-Transfer">[WS-Transfer]</a> resource, the <a href="#WS-Transfer">[WS-Transfer]</a> Put
     operation allows requesters to update the resource representation
     associated with that endpoint (i.e. the "data"), while the PutMetadata
     operation can be used to update that endpoint's metadata.
    </p><p>
     The normative outline for a PutMetadata request is:
    </p><div class="exampleOuter"><div class="exampleInner"><pre><b>[Action]</b>
  http://www.w3.org/2011/03/ws-mex/PutMetadata

<b>[Body]</b>
  &lt;mex:PutMetadata ...&gt;
    &lt;mex:Metadata ...&gt; ... &lt;/mex:Metadata&gt;
    <em>xs:any</em>*
  &lt;/mex:PutMetadata&gt;</pre></div></div><p>
     The following describes additional, normative constraints on the
     outline listed above:
    </p><dl><dt class="label"> <b>[Body]</b>/mex:PutMetadata </dt><dd><p>
        This REQUIRED element MUST have as its first child element an
        element that comprises the representation of the metadata that
        is to be replaced.  Additional extension elements MAY be included
        after the element representing the metadata to be updated.
       </p></dd><dt class="label"> <b>[Body]</b>/mex:PutMetadata/mex:Metadata </dt><dd><p>
        The body of the PutMetadata message MUST contain one
        mex:Metadata element as defined in
        <a href="#web-services-metadata"><b>4 Web Services Metadata Collection</b></a>.
       </p><p>
        The mex:Metadata element contains one MetadataSection child for
        each distinct unit of metadata to be updated.  All resource
        metadata (identified by the Dialect, Identifier and Content values)
        specified by
        each metadata section MUST be replaced in its entirety by the
        metadata specified in the PutMetadata request message;
        the service MUST treat the incoming MetadataSections as the
        complete set of metadata for the specified Dialect, Identifier and
        Content values and any metadata previously associated with that
        triplet of values MUST be removed.
       </p><p>
        If there is no Metadata associated with the resource that
        corresponds to a MetadataSection child contained within the
        mex:Metadata element, the endpoint MUST create the Metadata if
        the MetadataSection has a dialect that is supported by the
        endpoint and if the creation of the Metadata will not invalidate
        the endpoint.
       </p><p>
        When storing references, the endpoint
        MUST NOT resolve the references in an attempt to persist the
        actual metadata document itself.
       </p></dd></dl><p>
     An endpoint MUST reject a PutMetadata request if it is unable to
     process all of the metadata updates requested.   If the dialect,
     identifier or content form specified in one or more MetadataSections
     is unsupported
     by the endpoint, the endpoint MUST generate a mex:UnsupportedMetadata
     fault.
     If the creation or update of the endpoint's Metadata will render the
     endpoint invalid (either because the metadata is of an invalid syntax
     for the dialect or because the metadata will cause a semantic conflict
     with the endpoint's definition), the endpoint MUST generate an
     mex:InvalidMetadata fault.
    </p><p>
     If an endpoint accepts a PutMetadata request, it MUST reply with a
     PutMetadataResponse message. The normative outline for a
     PutMetadataResponse is:
    </p><div class="exampleOuter"><div class="exampleInner"><pre><b>[Action]</b>
  http://www.w3.org/2011/03/ws-mex/PutMetadataResponse

<b>[Body]</b>
  &lt;mex:PutMetadataResponse&gt;
    &lt;mex:Metadata ...&gt; ... &lt;/mex:Metadata&gt; ?
    <em>xs:any</em>*
  &lt;/mex:PutMetadataResponse&gt;</pre></div></div><p>
     The following describes additional, normative constraints on the
     outline listed above:
    </p><dl><dt class="label"> <b>[Body]</b>/mex:PutMetadataResponse </dt><dd><p>
        This REQUIRED element, if it contains any child elements, MUST have
        as its first child element, a mex:Metadata element that comprises
        the representation of the metadata that has been updated. Additional
        extension elements MAY be included after the element representing
        the metadata updates.
       </p><p>
        As an optimization and as a service to the requester, if there are
        no extension elements this element SHOULD be empty if the updated
        representation does not differ from the representation sent in
        the PutMetadata request message; that is, if the service accepted
        the new representation (including all Metadata updates) verbatim.
       </p><p>
        Such a response (an empty mex:PutMetadataResponse) implies that the
        update request was successful in its entirety (assuming no
        intervening mutating operations are performed). A service MAY return
        the current representation of the resource as the child of the
        mex:PutMetadataResponse element even in this case, however.
       </p></dd><dt class="label"> <b>[Body]</b>/mex:PutMetadataResponse/mex:Metadata </dt><dd><p>
        This OPTIONAL element comprises the representation of all the
        metadata sections of the resource that have been updated during
        the PutMetadata operation.
       </p></dd></dl></div><div class="div2">
<h3><a name="DeleteMetadata" id="DeleteMetadata"></a>6.4 DeleteMetadata</h3><p>
     A requester MAY send a DeleteMetadata request message to an endpoint
     to delete the metadata associated with that endpoint. This operation
     MAY be supported by WS-MetadataExchange compliant service endpoints.
     Observe that, in the case where a service endpoint is also a
     <a href="#WS-Transfer">[WS-Transfer]</a> resource, the <a href="#WS-Transfer">[WS-Transfer]</a>
     Delete operation allows requesters to update the resource representation
     associated with that endpoint (i.e. the "data"), while the
     DeleteMetadata operation can be used to update that endpoint's metadata.
    </p><p>
     The normative outline for a DeleteMetadata request is:
    </p><div class="exampleOuter"><div class="exampleInner"><pre><b>[Action]</b>
  http://www.w3.org/2011/03/ws-mex/DeleteMetadata

<b>[Body]</b>
  &lt;mex:DeleteMetadata ...&gt;
    &lt;mex:Dialect Type='<em>mex:QNameSerialization</em>'
                 Identifier='<em>xs:anyURI</em>'?
                 Content='<em>xs:anyURI</em>'? .../&gt; +
    <em>xs:any</em>*
  &lt;/mex:DeleteMetadata&gt;</pre></div></div><p>
     The following describes additional, normative constraints on the
     outline listed above:
    </p><dl><dt class="label"> <b>[Body]</b>/mex:DeleteMetadata </dt><dd><p>
        This REQUIRED element MUST have as its first children elements one
        or more elements that comprise the representation of the metadata
        that is to be deleted.  Additional extension elements MAY be
        included after the element representing the metadata to be deleted.
       </p></dd><dt class="label"> <b>[Body]</b>/mex:DeleteMetadata/mex:Dialect </dt><dd><p>
        This REQUIRED (optionally repeating) element specifies the
        metadata to be deleted.
       </p></dd><dt class="label"> <b>[Body]</b>/mex:DeleteMetadata/mex:Dialect@Type </dt><dd><p>
        This REQUIRED attribute specifies the Metadata Dialect of the
        metadata to be deleted.
       </p><p>
        Note: the QName is serialized as {namespace-uri}localName.
       </p></dd><dt class="label"> <b>[Body]</b>/mex:DeleteMetadata/mex:Dialect@Identifier </dt><dd><p>
        When this OPTIONAL attribute is present, only metadata with the
        indicated identifier is to be deleted.
        Absence of this attribute indicates that all metadata matching the
        specified Dialect and Content MUST be removed.
       </p></dd><dt class="label"> <b>[Body]</b>/mex:DeleteMetadata/mex:Dialect@Content </dt><dd><p>
        When this OPTIONAL attribute is present, only metadata of the
        specific content form is to be deleted.
        Absence of this attribute indicates that all metadata matching the
        specified Dialetc and Identifier MUST be removed.
       </p></dd></dl><p>
     An endpoint MUST reject a DeleteMetadata request if it is unable to
     process all of the metadata deletes requested.   If the dialect,
     identifier or content form
     specified in one or more of the Dialect elements is
     unsupported by the endpoint, the endpoint MUST generate a
     mex:UnsupportedMetadata fault.  If the deletion of the specified Metadata
     will render the endpoint invalid, the endpoint MUST generate an
     mex:InvalidMetadata fault.
     Note that an otherwise valid request that refers to metadata that does not
     exist is not considered an error condition. Rather, the service MUST
     continue as if it had successfully processed that one delete request.
    </p><p>
     If an endpoint accepts a DeleteMetadata request, it MUST reply with a
     DeleteMetadataResponse message. The normative outline for a
     DeleteMetadataResponse is:
    </p><div class="exampleOuter"><div class="exampleInner"><pre><b>[Action]</b>
  http://www.w3.org/2011/03/ws-mex/DeleteMetadataResponse

<b>[Body]</b>
  &lt;mex:DeleteMetadataResponse&gt;
    <em>xs:any</em>*
  &lt;/mex:DeleteMetadataResponse&gt;</pre></div></div><p>
     There are no additional, normative constraints on the outline listed above.
    </p></div></div><div class="div1">
<h2><a name="MetadataReferences" id="MetadataReferences"></a>7 Metadata References</h2><p>
    While a service's metadata can be embedded in many different places
    (for example, within an EPR, or within a feature's policy assertion),
    it might be more convenient to include a reference to the metadata rather
    than include the actual metadata itself. This might be simply for
    brevity's sake or so the same copy of metadata can be used in many
    different locations without the overhead of duplicating it.
   </p><p>
    This specification defines two mechanisms by which a metadata reference
    can be used in place of metadata. These mechanisms do not modify any
    semantic meaning that might be associated with the presence of the
    metadata at any particular location - they are simply a syntactical
    alternative to embedding the referenced metadata.
   </p><div class="div2">
<h3><a name="mexLocation" id="mexLocation"></a>7.1 mex:Location</h3><p>
     The mex:Location element MAY be used to specify a reference to an
     HTTP metadata resource. A requester MAY use an HTTP GET to the indicated
     URL to retrieve the metadata.
    </p><p>
     The outline for the mex:Location element is:
    </p><div class="exampleOuter"><div class="exampleInner"><pre>&lt;mex:Location URL="<em>xs:anyURI</em>" Type="<em>mex:QNameSerialization</em>"
              Identifier="<em>xs:anyURI</em>" ...&gt;
  <em>xs:any</em>*
&lt;mex:Location&gt; </pre></div></div><p>
     The following describes additional constraints on the outline listed
     above:
    </p><dl><dt class="label"> /mex:Location </dt><dd><p>
        This element contains a reference to an HTTP metadata resource.
       </p></dd><dt class="label"> /mex:Location@URL </dt><dd><p>
        This REQUIRED attribute contains the URL of an HTTP metadata
        resource. This resource MUST support retrieval of the metadata via
        an HTTP GET request.
       </p></dd><dt class="label"> /mex:Location@Type </dt><dd><p>
        This REQUIRED attribute indicates the QName of the referenced
        metadata. This can be used in deciding whether or not to retrieve
        the metadata.
       </p><p>
        Note: the QName is serialized as {namespace-uri}localName.
       </p></dd><dt class="label"> /mex:Location@Identifier </dt><dd><p>
        This REQUIRED attribute indicates the Identifier for the metadata
        being referenced. Identifier is an absolute IRI.
       </p></dd></dl></div><div class="div2">
<h3><a name="mexReference" id="mexReference"></a>7.2 mex:Reference</h3><p>
     The mex:Reference element MAY be used to specify a reference to a
     WS-Transfer metadata resource. A requester MAY use a WS-Transfer Get
     to the indicated EPR to retrieve the metadata
    </p><p>
     The outline for the mex:Reference element is:
    </p><div class="exampleOuter"><div class="exampleInner"><pre>&lt;mex:Reference Type="<em>mex:QNameSerialization</em>"
               Identifier="<em>xs:anyURI</em>" ...&gt;
  <em>endpoint-reference-type</em>
&lt;mex:Reference&gt; </pre></div></div><p>
     The following describes additional constraints on the outline listed
     above:
    </p><dl><dt class="label"> /mex:Reference </dt><dd><p>
        This element is an endpoint reference to a metadata resource. This
        resource MUST support retrieval of the metadata via a WS-Transfer
        Get request.
       </p></dd><dt class="label"> /mex:Reference@Type </dt><dd><p>
        This REQUIRED attribute indicates the QName of the referenced
        metadata. This can be used in deciding whether or not to retrieve
        the metadata.
       </p><p>
        Note: the QName is serialized as {namespace-uri}localName.
       </p></dd><dt class="label"> /mex:Reference@Identifier </dt><dd><p>
        This REQUIRED attribute indicates the Identifier for the metadata
        being referenced. Identifier is an absolute IRI.
       </p></dd></dl></div><div class="div2">
<h3><a name="idp1568496" id="idp1568496"></a>7.3 Examples</h3><p>
     The following examples show how metadata might appear in various
     locations:
    </p><div class="exampleOuter">
<div class="exampleHeader"><a name="WSDLinEPR" id="WSDLinEPR"></a>Example 7-1: WSDL in an Endpoint Reference</div><div class="exampleInner"><pre>(01) &lt;wsa:Endpoint ...&gt;
(02)    &lt;wsa:Address&gt; http://example.com &lt;/wsa:Address&gt;
(03)    &lt;wsa:Metadata&gt;
(04)      &lt;wsdl:definitions&gt;
(05)        ...
(06)      &lt;/wsdl:definitions&gt;
(07)    &lt;/wsa:Metadata&gt;
(08)  &lt;/wsa:Endpoint&gt; </pre></div></div><p>
     <a href="#WSDLinEPR">Example 7-1</a> shows an endpoint reference with the
     endpoint's WSDL embedded. This saves the user of this EPR from having
     to retrieve the WSDL. This same endpoint reference might have been
     constructed by using a metadata reference instead, as shown in
     <a href="#WSDLrefinEPR">Example 7-2</a>:
    </p><div class="exampleOuter">
<div class="exampleHeader"><a name="WSDLrefinEPR" id="WSDLrefinEPR"></a>Example 7-2: WSDL reference in an Endpoint Reference</div><div class="exampleInner"><pre>(01) &lt;wsa:Endpoint ...&gt;
(02)   &lt;wsa:Address&gt; http://example.com &lt;/wsa:Address&gt;
(03)   &lt;wsa:Metadata&gt;
(04)     &lt;mex:Location URL="http://example.com?wsdl"
(05)                     Type="{http://schemas.xmlsoap.org/wsdl/}definitions"
(06)                     Indentifier="..."/&gt;
(07)   &lt;/wsa:Metadata&gt;
(08) &lt;/wsa:Endpoint&gt; </pre></div></div><p>
     <a href="#WSDLrefinEPR">Example 7-2</a> shows the same endpoint reference but
     rather than embedding the endpoint's WSDL directly in the EPR a
     mex:Location is used to indicate that if the user of the EPR needs the
     service's WSDL then it can retrieve it from the specified URL.
    </p><p>
     The following example WSDL shows how support for a particular feature
     might be indicated:
    </p><div class="exampleOuter">
<div class="exampleHeader"><a name="idp1578208" id="idp1578208"></a>Example 7-3: Feature Metadata in a Policy Assertion</div><div class="exampleInner"><pre>(01) &lt;wsdl:definitions&gt;
(02)   ...
(03)   &lt;wsdl:service name="stockQuote"&gt;
(04)     &lt;wsdl:port binding="..." name="..."&gt;
(05)       &lt;soap:address location="http://example.com"/&gt;
(06)     &lt;/wsdl:port&gt;
(07)     &lt;wsp:Policy&gt;
(08)       &lt;wse:EventSource&gt;
(09)         &lt;wse:FormatName uri="http://www.w3.org/2011/03/ws-evt/DeliveryFormats/Unwrap"/&gt;
(10)         &lt;wsdl:definitions&gt;
(11)           ...
(12)           &lt;wsdl:service ...&gt;
(13)             ...
(14)             &lt;wsp:Policy xmlns:wsp="..." wmlns:sp="..."&gt;
(15)               &lt;sp:SymmetricBinding&gt;
(16)                 &lt;wsp:Policy&gt;
(17)                   &lt;sp:ProtectionToken&gt;
(18)                     &lt;wsp:Policy&gt;
(19)                       &lt;sp:SecureConversationToken ...&gt;
(20)                         ...
(21)                       &lt;/sp:SecureConversationToken&gt;
(22)                     &lt;/wsp:Policy&gt;
(23)                   &lt;/sp:ProtectionToken&gt;
(24)                 &lt;/wsp:Policy&gt;
(25)               &lt;/sp:SymmetricBinding&gt;
(26)             &lt;/wsp:Policy&gt;
(27)           &lt;/service&gt;
(28)         &lt;/wsdl:definitions&gt;
(29)       &lt;/wse:EventSource&gt;
(30)     &lt;/wsp:Policy&gt;
(31)   &lt;/wsdl:service&gt;
(32) &lt;/wsdl:definitions&gt; </pre></div></div><p>
     This example shows the WSDL for a stockQuote service. As indicated on
     lines (08) through (29), this endpoint also acts as a WS-Eventing event
     source.  The endpoint supports sending notification in the "Unwrapped"
     format - line (09).  Line (10) through (28) provides the WSDL for the
     WS-Eventing features. In particular, lines (14) through (26) indicates
     that the WS-Eventing messages need to be protected using
     WS-SecureConversation.
    </p><p>
     This example could have also been written by using metadata references:
    </p><div class="exampleOuter"><div class="exampleInner"><pre>(01) &lt;wsdl:definitions&gt;
(02)   ...
(03)   &lt;wsdl:service name="stockQuote"&gt;
(04)     &lt;wsdl:port binding="..." name="..."&gt;
(05)       &lt;soap:address location="http://example.com"/&gt;
(06)     &lt;/wsdl:port&gt;
(07)     &lt;wsp:Policy&gt;
(08)       &lt;wse:EventSource&gt;
(09)         &lt;wse:FormatName uri="http://www.w3.org/2011/03/ws-evt/DeliveryFormats/Unwrap"/&gt;
(10)         &lt;mex:Location URL="http://example.com/EventingWSDL"
(11)                       Type="{http://schemas.xmlsoap.org/wsdl/}definitions"
(12)                       Identifier="..." /&gt;
(13)       &lt;/wse:EventSource&gt;
(14)     &lt;/wsp:Policy&gt;
(15)   &lt;/wsdl:service&gt;
(16) &lt;/wsdl:definitions&gt; </pre></div></div><p>
     In this case the embedded WS-Eventing WSDL that is supported by the
     stockQuote service has been replaced by a mex:Location element. The WSDL
     can now be retrieved via an HTTP GET to the URL specified on line (10).
    </p></div></div><div class="div1">
<h2><a name="Metadata-in-Endpoint-References" id="Metadata-in-Endpoint-References"></a>8 Metadata in Endpoint References</h2><div class="div2">
<h3><a name="EPRwithMEX" id="EPRwithMEX"></a>8.1 Endpoint References Containing Metadata</h3><p>
     The issuer of a WS-Addressing endpoint
     reference MAY include metadata for that service inside
     the endpoint reference itself. This mechanism
     simplifies the bootstrapping of the service interaction on the
     requester side by avoiding additional calls to retrieve
     the Web service metadata for the service endpoint.
    </p><p>
     Embedding the metadata (including a mex:Metadata element) inside an
     endpoint reference's wsa:Metadata element allows
     the issuer of the endpoint reference to include metadata by value
     or by reference, according to the options described in
     <a href="#web-services-metadata"><b>4 Web Services Metadata Collection</b></a> and
     <a href="#MetadataReferences"><b>7 Metadata References</b></a>.
     The outline of a <a href="#AddrCore">[WS-Addressing]</a> endpoint reference which
     includes Web services metadata is as follows:
    </p><div class="exampleOuter"><div class="exampleInner"><pre>&lt;wsa:EndpointReference ...&gt;
     &lt;wsa:Address&gt;xs:anyURI&lt;/wsa:Address&gt;
     &lt;wsa:ReferenceParameters&gt; <em>xs:any</em>* &lt;/wsa:ReferenceParameters&gt; ?
     &lt;wsa:Metadata&gt;
       ( &lt;mex:Location .../&gt; |
         &lt;mex:Reference ...&gt; ... &lt;/mex:Reference&gt; |
         &lt;mex:Metadata ...&gt; ... &lt;/mex:Metadata&gt; ) *
         <em>xs:any</em>*
     &lt;/wsa:Metadata&gt; ?
     <em>xs:any</em>*
&lt;/wsa:EndpointReference&gt;</pre></div></div><dl><dt class="label"> /wsa:EndpointReference/wsa:Metadata/mex:Location </dt><dd><p>
        This repeating OPTIONAL element MAY appear as a direct child of
        the wsa:Metadata endpoint reference element.
       </p></dd><dt class="label"> /wsa:EndpointReference/wsa:Metadata/mex:Reference </dt><dd><p>
        This repeating OPTIONAL element MAY appear as a direct child of
        the wsa:Metadata endpoint reference element.
       </p></dd><dt class="label"> /wsa:EndpointReference/wsa:Metadata/mex:Metadata </dt><dd><p>
        This repeating OPTIONAL element MAY appear as a direct child of
        the wsa:Metadata endpoint reference element.
        Note: It MAY also be possible to combine multiple mex:Metadata
        elements into one mex:Metadata element, however, it is RECOMMENDED
        that multiple mex:Metadata elements be used.
       </p></dd><dt class="label"> /wsa:EndpointReference/wsa:Metadata/xs:any </dt><dd><p>
        This extensibility point, defined by WS-Addressing, can be used
        for embedding additional metadata.
       </p></dd></dl><p>
     In example <a href="#EPRMEX">Example 8-1</a>, a <a href="#AddrCore">[WS-Addressing]</a>
     endpoint reference contains WSDL metadata by value that identifies
     the binding used to access the service endpoint:
    </p><div class="exampleOuter">
<div class="exampleHeader"><a name="EPRMEX" id="EPRMEX"></a>Example 8-1: Endpoint reference with embedded WSDL metadata</div><div class="exampleInner"><pre>(01) &lt;wsa:EndpointReference
(02)     xmlns:wsa='http://www.w3.org/2005/08/addressing'&gt;
(03)   &lt;wsa:Address&gt;http://services.example.org/stockquote&lt;/wsa:Address&gt;
(04)   &lt;wsa:Metadata&gt;
(05)     &lt;wsdl:definitions
(06)         name='StockQuote'
(07)         targetNamespace='http://services.example.org/stockquote'
(08)         xmlns:tns='http://services.example.org/stockquote'
(09)         xmlns:wsoap='http://schemas.xmlsoap.org/wsdl/soap/'
(10)         xmlns:wsdl='http://schemas.xmlsoap.org/wsdl/'
(11)         xmlns:wsp='http://www.w3.org/ns/ws-policy'
(12)         xmlns:msgs='http://services.example.org/stockquote/schemas
(13)         xmlns:xs='http://www.w3.org/2001/XMLSchema'&gt;
(14)       &lt;wsdl:import
(15)           namespace='http://services.example.org/stockquote'
(16)           location='http://services.example.org/stockquote/schemas'/&gt;
(17)       &lt;wsdl:portType name='StockQuotePortType'&gt;
(18)         &lt;wsdl:operation name='GetLastTradePrice'&gt;
(19)           &lt;wsdl:input message='msgs:GetLastTradePriceInput'
(20)                       name='GetLastTradePriceInput'/&gt;
(21)           &lt;wsdl:output message='msgs:GetLastTradePriceOutput'
(22)                        name='GetLastTradePriceOutput'/&gt;
(23)         &lt;/wsdl:operation&gt;
(24)       &lt;/wsdl:portType&gt;
(25)       &lt;wsdl:binding name='StockQuoteBinding'
(26)             type='tns:StockQuotePortType'&gt;
(27)         &lt;wsp:PolicyReference
(28)             URI='http://services.example.org/stockquote/policy' /&gt;
(29)         &lt;wsoap:binding style='document'
(30)                  transport='http://schemas.xmlsoap.org/soap/http'/&gt;
(31)         &lt;wsdl:operation name='GetLastTradePrice'&gt;
(32)           &lt;wsoap:operation soapAction='http://services.example.org/stockquote/GetLastTradePrice' /&gt;
(33)           &lt;wsdl:input name='GetLastTradePriceInput'&gt;
(34)             &lt;wsoap:body use='literal'/&gt;
(35)           &lt;/wsdl:input&gt;
(36)           &lt;wsdl:output name='GetLastTradePriceOutput'&gt;
(37)             &lt;wsoap:body use='literal'/&gt;
(38)           &lt;/wsdl:output&gt;
(39)         &lt;/wsdl:operation&gt;
(40)       &lt;/wsdl:binding&gt;
(41)       &lt;wsdl:service name='StockQuoteService'&gt;
(42)         &lt;wsdl:port name='StockQuotePort'
(43)                    binding='tns:StockQuoteBinding' &gt;
(44)           &lt;wsoap:address
(45)                 location='http://services.example.org/stockquote'/&gt;
(46)         &lt;/wsdl:port&gt;
(47)       &lt;/wsdl:service&gt;
(48)     &lt;/wsdl:definitions&gt;
(49)   &lt;/wsa:Metadata&gt;
(50) &lt;/wsa:EndpointReference&gt; </pre></div></div><p>
     Lines 5-48 show the way the WSDL of the Web service endpoint is
     included 'by value'.
    </p><div class="exampleOuter">
<div class="exampleHeader"><a name="EPRMD" id="EPRMD"></a>Example 8-2: Endpoint reference with embedded metadata about the Metadata Reference</div><div class="exampleInner"><pre>(01) &lt;wsa:EndpointReference ...&gt;
(02)   &lt;wsa:Address&gt;http://services.example.org/stockquote&lt;/wsa:Address&gt;
(03)   &lt;wsa:Metadata&gt;
(04)     &lt;mex:Reference Type="{http://www.w3.org/2011/03/ws-mex}Metadata" Identifier=""&gt;
(05)       &lt;wsa:Address&gt;
(06)         http://services.example.org/stockquote/metadata
(07)       &lt;/wsa:Address&gt;
(08)       &lt;wsa:Metadata&gt;
(09)         &lt;wsdl:definitions ...&gt;
(10)           &lt;!-- WS-Transfer WSDL portType plus binding --&gt;
(11)         &lt;/wsdl:definitions&gt;
(12)       &lt;/wsa:Metadata&gt;
(13)     &lt;/mex:Reference&gt;
(14)   &lt;/wsa:Metadata&gt;
(15) &lt;/wsa:EndpointReference&gt; </pre></div></div><p>
     <a href="#EPRMD">Example 8-2</a> shows an example of a Web service endpoint
     reference in which the Metadata element contains a single
     mex:Reference element to a metadata resource (lines 4-13) the
     representation of which is mex:Metadata as hinted by the value of
     the Type attribute (line 4). The metadata reference contains a
     Metadata element (lines 8-12) which contains the necessary metadata for
     interacting with the metadata resource through
     <a href="#WS-Transfer">[WS-Transfer]</a> operations. Since the mex:Reference
     is an endpoint reference to a <a href="#WS-Transfer">[WS-Transfer]</a>
     resource, the embedded metadata includes the <a href="#WS-Transfer">[WS-Transfer]</a>
     WSDL portType and the necessary binding information for communicating
     with that resource.
    </p><div class="exampleOuter">
<div class="exampleHeader"><a name="EPRrefMDref" id="EPRrefMDref"></a>Example 8-3: Endpoint reference with a reference to metadata about the Metadata Reference</div><div class="exampleInner"><pre>(01) &lt;wsa:EndpointReference ...&gt;
(02)   &lt;wsa:Address&gt;http://services.example.org/stockquote&lt;/wsa:Address&gt;
(03)   &lt;wsa:Metadata&gt;
(04)     &lt;mex:Reference Type='{http://www.w3.org/2011/03/ws-mex}Metadata' Identifier=''&gt;
(05)       &lt;wsa:Address&gt;
(06)         http://services.example.org/stockquote/metadata
(07)       &lt;/wsa:Address&gt;
(08)       &lt;wsa:Metadata&gt;
(09)         &lt;!-- Ref to the WS-Transfer WSDL --&gt;
(10)         &lt;mex:Location URL='http://example.org/sq/TransferWSDL'
(11)                       Type='{http://schemas.xmlsoap.org/wsdl/}definitions' Identifier='...'/&gt;
(12)       &lt;/wsa:Metadata&gt;
(13)     &lt;/mex:Reference&gt;
(14)   &lt;/wsa:Metadata&gt;
(15) &lt;/wsa:EndpointReference&gt; </pre></div></div><p>
     <a href="#EPRrefMDref">Example 8-3</a> shows an alternative way to represent
     <a href="#EPRMD">Example 8-2</a>. It shows an example of a Web service endpoint
     reference in which the Metadata element contains a single mex:Reference
     element to a metadata resource (lines 4-13) the representation of which
     is mex:Metadata as hinted by the value of the Type attribute (line 4).
     The metadata reference contains a Metadata element (lines 8-12) which
     contains the necessary metadata for interacting with the metadata
     resource through <a href="#WS-Transfer">[WS-Transfer]</a> operations. Since the
     mex:Reference is an endpoint reference to a <a href="#WS-Transfer">[WS-Transfer]</a>
     resource, the mex:Location element is a reference to the
     <a href="#WS-Transfer">[WS-Transfer]</a> WSDL which includes the portType and the
     necessary binding information for communicating with that resource.
    </p><p>
     In example <a href="#EPR-PA">Example 8-4</a>, an endpoint reference to a service
     endpoint contains the metadata to allow requesters to issue a GetWSDL
     request against it.
    </p><div class="exampleOuter">
<div class="exampleHeader"><a name="EPR-PA" id="EPR-PA"></a>Example 8-4: Endpoint reference containing Policy Attachment metadata for the GetWSDL operation</div><div class="exampleInner"><pre>(01) &lt;wsa:EndpointReference ...&gt;
(02)   &lt;wsa:Address&gt;http://services.example.org/stockquote&lt;/wsa:Address&gt;
(03)   &lt;wsa:Metadata&gt;
(04)     &lt;wsp:PolicyAttachment&gt;
(05)       &lt;wsp:AppliesTo&gt;
(06)         &lt;!-- Following according to: http://www.w3.org/TR/ws-policy-attach/#uri-domain-expression --&gt;
(07)         &lt;!-- with URI syntax from:
(08)              http://www.w3.org/TR/wsdl11elementidentifiers/ --&gt;
(09)         &lt;wsp:URI&gt;
(10)           http://www.w3.org/2011/03/ws-mex#wsdl1.PortTypeOperation(GetWSDL)
(11)         &lt;/wsp:URI&gt;
(12)       &lt;/wsp:AppliesTo&gt;
(13)       &lt;wsp:Policy&gt; ... &lt;/wsp:Policy&gt;
(14)     &lt;/wsp:PolicyAttachment&gt;
(15)   &lt;/wsa:Metadata&gt;
(16) &lt;/wsa:EndpointReference&gt; </pre></div></div><p>
     <a href="#EPR-PA">Example 8-4</a> shows an example of an endpoint reference to a
     service endpoint.  The endpoint reference contains metadata associated
     with the service endpoint (lines 3-15) and the Policy metadata
     (lines 4-14) which contains the necessary metadata for interacting
     with the endpoint through WS-MetadataExchange.  The metadata for
     the WS-MetadataExchange interaction is of policy attachment (line 4).
     The policy attachment (lines 4-14) defines the policy (line 13) and
     the GetWSDL operation to which the policy applies (lines 5-12).
    </p><p>
     Alternatively, <a href="#EPR-PA">Example 8-4</a> could have been written with
     the WS-MetadataExchange Policy Assertion embedded directly into the
     EPR along with the necessary Policy Assertions, as shown in
     <a href="#EPRmexAssertion">Example 8-5</a>:
    </p><div class="exampleOuter">
<div class="exampleHeader"><a name="EPRmexAssertion" id="EPRmexAssertion"></a>Example 8-5: Endpoint reference containing the MetadataExchange policy assertion</div><div class="exampleInner"><pre>(01) &lt;wsa:EndpointReference ...&gt;
(02)   &lt;wsa:Address&gt;http://services.example.org/stockquote&lt;/wsa:Address&gt;
(03)   &lt;wsa:Metadata&gt;
(04)     &lt;wsp:Policy&gt;
(05)       &lt;mex:MetadataExchange&gt;
(06)         &lt;wsp:Policy&gt; ... &lt;/wsp:Policy&gt;
(07)       &lt;/mex:MetadataExchange&gt;
(08)     &lt;/wsp:Policy&gt;
(09)   &lt;/wsa:Metadata&gt;
(10) &lt;/wsa:EndpointReference&gt; </pre></div></div><p>
     <a href="#EPRmexAssertion">Example 8-5</a> shows an example of a endpoint
     reference to a service endpoint. The endpoint reference contains
     Policy metadata that can be used to properly interact with the service.
     In this case the Policy contains the mex:MetadataExchange Policy
     Assertion (lines 5-7) indicating that it supports the WS-MetadataExchange
     specification.  Line 6 contains a Policy Assertion that further qualifies
     how a requester would invoke the WS-MetadataExchange operations.  For
     example, the Policy Assertion on line 6 might contain
     assertions to indicate how all WS-MetadataExchange messages are to
     be consturcted.
    </p></div><div class="div2">
<h3><a name="WSPAEPR" id="WSPAEPR"></a>8.2 Associating Policies with Endpoint References</h3><p>
     It is desirable for components that provide EPRs to other components to
     be able to efficiently communicate the effective policies of the
     endpoints referenced by those EPRs. For example, a subscriber might wish
     to indicate to an event source that the notification messages sent as
     part of a subscription needs to be digitally signed. Although the
     mechanisms described in <a href="#EPRwithMEX"><b>8.1 Endpoint References Containing Metadata</b></a> can be used to
     communicate the complete set of policies associated with an endpoint,
     the relationship of these policies to specific bindings, operations,
     or messages cannot be determined without additional information such
     as WSDL documents or wsp:PolicyAttachment elements.
    </p><p>
     A single wsp:Policy or wsp:PolicyReference element MAY appear as a
     child of the /wsa:EndpointReference/wsa:Metadata element.
    </p><div class="exampleOuter"><div class="exampleInner"><pre>&lt;wsa:EndpointReference&gt;
  &lt;wsa:Address&gt; xs:anyURI &lt;/wsa:Address&gt;
  &lt;wsa:ReferenceParameters&gt; xs:any* &lt;/wsa:ReferenceParameters&gt;
  &lt;wsa:Metadata&gt;
    ( &lt;wsp:Policy ...&gt; ... &lt;/wsp:Policy&gt; |
      &lt;wsp:PolicyReference ...&gt; ... &lt;/wsp:PolicyReference&gt; ) ?
  &lt;/wsa:Metadata&gt;
&lt;/wsa:EndpointReference&gt;</pre></div></div><p>
     If multiple alternatives are desired, the operators defined in
     <a href="#wspolicy">[WS-Policy]</a> can be used to specify such alternatives
     within the single wsp:Policy element or the element referenced by the
     wsp:PolicyReference.
    </p><p>
     Policies that appear in an endpoint reference in this manner have
     Endpoint Policy Subject. Endpoint Policy Subject is defined as follows:
    </p><p>
     The wsp:Policy or wsp:PolicyReference element, when present, represents
     the capabilities and requirements of the endpoint referenced by the
     EPR as defined by Section 3, "Policy Model", in the
     <a href="#wspolicy">[WS-Policy]</a> specification. Policy attached to an EPR in
     this manner MUST be applicable to all message exchanges using the
     endpoint referenced by that EPR.
    </p><div class="exampleOuter">
<div class="exampleHeader"><a name="EPRsecure" id="EPRsecure"></a>Example 8-6: Endpoint Reference with Associated Policy</div><div class="exampleInner"><pre>(01) &lt;wse:NotifyTo xmlns:wsa="http://www.w3.org/2005/08/addressing"
(02)               xmlns:wse="http://www.w3.org/2011/03/ws-evt"&gt;
(03)   &lt;wsa:Address&gt;http://www.example.com/EventSink/OnPriceChange&lt;/wsa:Address&gt;
(04)   &lt;wsa:ReferenceParameters&gt;
(05)     ...
(06)   &lt;/wsa:ReferenceParameters&gt;
(07)   &lt;wsa:Metadata&gt;
(08)     &lt;wsp:Policy xmlns:wsp="..." wmlns:sp="..."&gt;
(09)       &lt;sp:SymmetricBinding&gt;
(10)         &lt;wsp:Policy&gt;
(11)           &lt;sp:ProtectionToken&gt;
(12)             &lt;wsp:Policy&gt;
(13)               &lt;sp:SecureConversationToken ...&gt;
(14)                 ...
(15)               &lt;/sp:SecureConversationToken&gt;
(16)             &lt;/wsp:Policy&gt;
(17)           &lt;/sp:ProtectionToken&gt;
(18)         &lt;/wsp:Policy&gt;
(19)       &lt;/sp:SymmetricBinding&gt;
(20)     &lt;/wsp:Policy&gt;
(21)   &lt;/wsa:Metadata&gt;
(22) &lt;/wse:NotifyTo&gt;</pre></div></div><p>
     <a href="#EPRsecure">Example 8-6</a> shows a WS-Eventing NotifyTo EPR that refers
     to the endpoint to which an event source sends notification messages.
     Attached to this EPR is a Policy (lines 8-20) that indicates that
     WS-SecureConversation needs to be used when sending messages to
     this endpoint.
    </p><p>
     Note that in some cases the context in which an EPR appears might
     imply the version of SOAP that messages addressed to that EPR are to
     use.  In this example, without an explicit use of the SOAP assertion,
     the Notifications will most likely be sent using the same version of
     SOAP that was used to carry the Subscribe message.
    </p><p>
     The <a href="#AddrCore">[WS-Addressing]</a> specification discusses caveats to the
     validity of Metadata information. These apply to policies contained
     within the wsa:Metadata element as discussed in this section.
    </p><p>
     The relationship, if any, between policies contained within the
     wsa:Metadata element and any other policies that might apply to the
     endpoint referred to by the containing EPR (e.g. policies that might
     appear in a WSDL document that describes one or more of the services
     offered by that endpoint) is not defined by this specification.
    </p></div></div><div class="div1">
<h2><a name="ImplicitWSDL" id="ImplicitWSDL"></a>9 Exposing Metadata for Implicitly Defined Features</h2><p>
    An endpoint MAY indicate that it supports a specific feature by
    including the feature's policy assertion within its WSDL. By doing so,
    the endpoint is indicating that feature operations are
    supported by that endpoint even though they are implicit
    and do not explicitly appear in
    its WSDL.  An example of this is an endpoint that indicates the use
    of WS-Transfer <a href="#WS-Transfer">[WS-Transfer]</a> by the use of the
    wst:TransferResource WS-Policy <a href="#wspolicy">[WS-Policy]</a> assertion.
   </p><p>
    The Feature WSDL (the WSDL associated with these implicit operations)
    MAY appear within a Feature Policy assertion and can be annotated to
    indicate any endpoint specific metadata that might be needed by clients
    interacting with this service. For example, the WSDL can have policy
    assertions that indicate a particular security mechanism used to protect
    the feature's operations supported by this endpoint. When a Feature WSDL
    does not provide a concrete endpoint, the consumer MUST use the
    concrete aspects of the endpoint's WSDL.
   </p><p>
    An endpoint MAY choose to expose additional metadata about the feature
    by including the feature specific metadata within the feature's policy
    assertion.  For example, an endpoint that also supports WS-Eventing
    might choose to have the following WS-Eventing Policy assertion defined:
   </p><div class="exampleOuter">
<div class="exampleHeader"><a name="wseEventSourcePA" id="wseEventSourcePA"></a>Example 9-1: WS-Eventing EventSource Policy Assertion with Annotations</div><div class="exampleInner"><pre>(01) &lt;wsp:Policy&gt;
(02)  &lt;wse:EventSource&gt;
(03)   &lt;wse:FormatName
(04)     URI="http://www.w3.org/2011/03/ws-evt/DeliveryFormats/Unwrap"&gt;
(05)   &lt;/wse:FormatName&gt;
(06)   &lt;wsevd:EventDescriptions&gt;
(07)    &lt;wsevd:types&gt;
(08)     &lt;xs:schema targetNamespace="http://www.example.org/oceanwatch"&gt;
(09)      &lt;xs:include
(10)       schemaLocation="http://www.example.org/schemas/oceanwatch.xsd"/&gt;
(11)      &lt;xs:element name="WindReport" type="ow:WindReportType"/&gt;
(12)     &lt;/xs:schema&gt;
(13)    &lt;/wsevd:types&gt;
(14)    &lt;wsevd:eventType name="WindReportEvent" element="ow:WindReport"
(15)      actionURI="http://www.example.org/oceanwatch/2003/WindReport"/&gt;
(16)   &lt;/wsevd:EventDescriptions&gt;
(17)   &lt;wsp:Policy&gt; ...security policies... &lt;/wsp:Policy&gt;
(18)  &lt;/wse:EventSource&gt;
(19) &lt;/wsp:Policy&gt; </pre></div></div><p>
    When this policy assertion appears in a service's WSDL it indicates that
    the service supports WS-Eventing, it supports sending notifications using
    the 'Unwrap' format, and that it generates exactly one type of event -
    a &lt;sq:Quote&gt; event. The Policy Assertion on line 17 indicates that the
    nested policy assertions apply to the WS-Eventing operations. For
    example, if line 17 includes some security related assertions then the
    WS-Eventing operations would need to be secured using those security
    mechanisms.
   </p><p>
    When Feature Policy Assertions contain nested Policy Assertions (as
    show above in line 17), those assertions have Endpoint Policy Subject
    and apply to all message exchanges related to the feature.
   </p><p>
    If there were additional WS-Eventing metadata available, for example
    a specialized Feature WSDL document, then they would appear as a child
    of the wse:EventSource element as well.
   </p><p>
    The following shows the same WS-Eventing Policy Assertion from
    <a href="#wseEventSourcePA">Example 9-1</a> with an embedded copy of the
    WS-Eventing WSDL.  As discussed above, this WSDL might be annotated to
    specify additional constrains on the WS-Eventing message exchanges.
   </p><div class="exampleOuter">
<div class="exampleHeader"><a name="idp1649120" id="idp1649120"></a>Example 9-2:  Sample WS-Eventing Policy with Embedded WSDL </div><div class="exampleInner"><pre>(01) &lt;wsp:Policy&gt;
(02)  &lt;wse:EventSource&gt;
(03)   &lt;wse:FormatName
(04)     URI="http://www.w3.org/2011/03/ws-evt/DeliveryFormats/Unwrap"&gt;
(05)   &lt;/wse:FormatName&gt;
(06)   &lt;wsevd:EventDescriptions&gt;
(07)    &lt;wsevd:types&gt;
(08)     &lt;xs:schema targetNamespace="http://www.example.org/oceanwatch"&gt;
(09)      &lt;xs:include
(10)       schemaLocation="http://www.example.org/schemas/oceanwatch.xsd"/&gt;
(11)      &lt;xs:element name="WindReport" type="ow:WindReportType"/&gt;
(12)     &lt;/xs:schema&gt;
(13)    &lt;/wsevd:types&gt;
(14)    &lt;wsevd:eventType name="WindReportEvent" element="ow:WindReport"
(15)      actionURI="http://www.example.org/oceanwatch/2003/WindReport"/&gt;
(16)   &lt;/wsevd:EventDescriptions&gt;
(17)   &lt;wsdl:definitions&gt; ...ws-eventing wsdl... &lt;/wsdl:definitions&gt;
(18)  &lt;/wse:EventSource&gt;
(19) &lt;/wsp:Polixy&gt; </pre></div></div><p>
    The following shows a sample WS-Eventing wse:NotifyTo endpoint
    reference that might appear as part of a Subscribe request. Lines 05-08
    indicate that WS-ReliableMessaging is required when sending notifications
    to this endpoint. The mex:Location element, lines 06-07, is a reference
    to the WS-ReliableMessaging WSDL that the event source will need to use
    when transmitting the WS-ReliableMessaging protocol messages for those
    notifications.  For example, this WSDL might include security policy
    assertions or perhaps binding information that indicates there is a
    specific endpoint to which those protocol messages are to be sent - if
    it is different from the address specified on line 02.
   </p><div class="exampleOuter">
<div class="exampleHeader"><a name="idp1651216" id="idp1651216"></a>Example 9-3:  Sample EndpointReference with Embedded Policy </div><div class="exampleInner"><pre>(01) &lt;wse:NotifyTo&gt;
(02)   &lt;wsa:Address&gt; http://example.com &lt;/wsa:Address&gt;
(03)   &lt;wsa:Metadata&gt;
(04)     &lt;wsp:Policy&gt;
(05)       &lt;wsrmp:RMAssertion&gt;
(06)         &lt;mex:Location URL='http://example.com/RMWSDL'
(07)                       Type='{http://schemas.xmlsoap.org/wsdl/}definitions' Identifier='...'/&gt;
(08)       &lt;/wsrmp:RMAssertion&gt;
(09)     &lt;/wsp:Policy&gt;
(10)   &lt;/wsa:Metadata&gt;
(11) &lt;/wse:NotifyTo&gt; </pre></div></div></div><div class="div1">
<h2><a name="Faults" id="Faults"></a>10 Faults</h2><p>
    All fault messages defined in this specification MUST be sent
    according to the rules and usage described in
    <a href="#WSABinding">[WS-Addressing 1.0 SOAP Binding]</a>
    Section 6 for encoding SOAP 1.1 and SOAP 1.2 faults.
    The <b>[Action]</b> property below MUST be used for faults
    defined in this specification:
   </p><div class="exampleOuter"><div class="exampleInner"><pre><a href="http://www.w3.org/2011/03/ws-mex/fault">http://www.w3.org/2011/03/ws-mex/fault</a></pre></div></div><p>
    The definitions of faults in this section use the following properties:
   </p><p>
    <b>[Code]</b> The fault code.<br />
    <b>[Subcode]</b> The fault subcode.<br />
    <b>[Reason]</b> The English language reason element.<br />
    <b>[Detail]</b> The detail element. If absent, no detail element
    is defined for the fault.<br />
   </p><p>The properties above bind to a SOAP 1.2 fault as follows:</p><div class="exampleOuter"><div class="exampleInner"><pre>&lt;s12:Envelope&gt;
  &lt;s12:Header&gt;
    &lt;wsa:Action&gt; <b>[Action]</b> &lt;/wsa:Action&gt;
    &lt;!-- Headers elided for brevity. --&gt;
  &lt;/s12:Header&gt;
  &lt;s12:Body&gt;
    &lt;s12:Fault&gt;
      &lt;s12:Code&gt;
        &lt;s12:Value&gt;<b>[Code]</b>&lt;/s12:Value&gt;
        &lt;s12:Subcode&gt;
          &lt;s12:Value&gt;<b>[Subcode]</b>&lt;/s12:Value&gt;
        &lt;/s12:Subcode&gt;
      &lt;/s12:Code&gt;
      &lt;s12:Reason&gt;
        &lt;s12:Text xml:lang="en"&gt;<b>[Reason]</b>&lt;/s12:Text&gt;
      &lt;/s12:Reason&gt;
      &lt;s12:Detail&gt;
        <b>[Detail]</b>
        ...
      &lt;/s12:Detail&gt;
    &lt;/s12:Fault&gt;
  &lt;/s12:Body&gt;
&lt;/s12:Envelope&gt;</pre></div></div><p>The properties bind to a SOAP 1.1 fault as follows:</p><div class="exampleOuter"><div class="exampleInner"><pre>&lt;s11:Envelope&gt;
  &lt;s12:Header&gt;
    &lt;wsa:Action&gt; <b>[Action]</b> &lt;/wsa:Action&gt;
    &lt;!-- Headers elided for brevity. --&gt;
  &lt;/s12:Header&gt;
  &lt;s11:Body&gt;
    &lt;s11:Fault&gt;
      &lt;faultcode&gt;<b>[Subcode]</b>&lt;/faultcode&gt;
      &lt;faultstring xml:lang="en"&gt;<b>[Reason]</b>&lt;/faultstring&gt;
      &lt;detail&gt;
        <b>[Detail]</b>
        ...
      &lt;/detail&gt;
    &lt;/s11:Fault&gt;
  &lt;/s11:Body&gt;
&lt;/s11:Envelope&gt;</pre></div></div><div class="div2">
<h3><a name="UnsupportedMetadata" id="UnsupportedMetadata"></a>10.1 UnsupportedMetadata</h3><p>
     This fault MUST be generated when one or more metadata dialect(s)
     specified on the request message are unsupported by the endpoint.
    </p><table border="1"><tbody><tr><th align="left"><b>[Code]</b></th><td>s:Sender</td></tr><tr><th align="left"><b>[Subcode]</b></th><td>mex:UnsupportedMetadata</td></tr><tr><th align="left"><b>[Reason]</b></th><td>
        The metadata specified on the request message is not supported by
        the endpoint
       </td></tr><tr><th align="left"><b>[Detail]</b></th><td>
        <em>One or more elements specifying the unsupported Metadata of the
        following form:</em>
        <br />
        &lt;Dialect Type='<em>mex:QNameSerialization</em>' Identifier='<em>xs:anyURI</em>'? .../&gt; +
       </td></tr></tbody></table></div><div class="div2">
<h3><a name="InvalidMetadata" id="InvalidMetadata"></a>10.2 InvalidMetadata</h3><p>
     This fault MUST be generated when the metadata passed on the
     PutMetadata request message is invalid or when the Metadata would
     render the endpoint invalid.
    </p><table border="1"><tbody><tr><th align="left"><b>[Code]</b></th><td>s:Sender</td></tr><tr><th align="left"><b>[Subcode]</b></th><td>mex:InvalidMetadata</td></tr><tr><th align="left"><b>[Reason]</b></th><td>
        The metadata specified is invalid for this endpoint
       </td></tr><tr><th align="left"><b>[Detail]</b></th><td>
        <em>The invalid metadata specified by a mex:Metadata element.</em>
        <br />
        &lt;mex:Metadata ...&gt; ... &lt;/mex:Metadata&gt;
       </td></tr></tbody></table></div></div><div class="div1">
<h2><a name="Security" id="Security"></a>11 Security Considerations</h2><p>
    This specification considers two sets of security requirements, those of
    the applications that use the WS-MetadataExchange protocol and those of
    the protocol itself.
   </p><p>
    This specification makes no assumptions about the security requirements
    of the applications that use WS-MetadataExchange. However, once those
    requirements have been satisfied within a given operational context,
    the addition of WS-MetadataExchange to this operational context can
    not undermine the fulfillment of those requirements; the use of
    WS-MetadataExchange SHOULD NOT create additional attack vectors within
    an otherwise secure system.
   </p><p>
    The material below is not a "check list". There are many other security
    concerns that need to be considered when implementing or using this
    protocol. Implementers and users of this protocol are urged to perform a
    security analysis to determine their particular threat profile and the
    appropriate responses to those threats.
   </p><div class="div2">
<h3><a name="idp1702016" id="idp1702016"></a>11.1 Metadata and Security Bootstrapping</h3><p>
     There are cases in which the metadata used to describe a service might
     be considered sensitive information. In these cases it is advisable
     for services to authenticate and authorize consumers as part of the
     processing of any requests for this metadata. However, because the
     security aspects of a service (e.g. supported protocols and token
     formats, cipher suites, etc.) are usually described using metadata
     (i.e. the constructs defined by WS-SecurityPolicy), there is an obvious
     dilemma when attempting to protect metadata in this way. Services
     wishing to protect access to their metadata are advised to use the
     mechanisms described in <a href="#bootstrapping"><b>13 Bootstrapping Metadata Retrieval</b></a> to advertise
     the security requirements for clients wishing to access metadata via
     the mechanisms defined in this specification.
    </p></div></div><div class="div1">
<h2><a name="metadata" id="metadata"></a>12 WS-MetadataExchange Metadata</h2><p>
    An endpoint MAY indicate its support of WS-MetadataExchange, or its
    features,
    by including the MetadataExchange Policy assertion within its WSDL. By
    doing so the endpoint is indicating that the corresponding
    WS-MetadataExchange
    operations are supported by that endpoint even though they are implicit
    and do not explicitly appear in its WSDL
    (i.e. the WS-MetadataExchange operations do not appear in the WSDL that
    MAY be retrievable by using a WS-MetadataExchange GetWSDL to that endpoint).
   </p><p>
    The WS-MetadataExchange WSDL containing the operations indicated by the
    MetadataExchange Assertion MAY be exposed by including the WSDL as a
    child of the MetadataExchange Policy assertion or by including a
    reference to it using the mex:Location or mex:Reference elements
    (as described in <a href="#MetadataReferences"><b>7 Metadata References</b></a>).
   </p><p>
    The WS-MetadataExchange WSDL can be annotated to indicate any endpoint
    specific metadata that might be needed by clients interacting with
    the WS-MetadataExchange operations.  For example, the WSDL
    MAY have policy assertions that
    indicate a particular security mechanism used to protect the
    WS-MetadataExchange operations supported by this endpoint.
   </p><div class="div2">
<h3><a name="idp1708960" id="idp1708960"></a>12.1 MetadataExchange Assertion</h3><p>
     Services indicate support for the WS-MetadataExchange specification
     through the use of the Web Services
     Policy - Framework <a href="#wspolicy">[WS-Policy]</a> and Web Services Policy -
     Attachment <a href="#WS-PolicyAttachment">[WS-PolicyAttachment]</a> specifications.
    </p><p>
     This specification defines a policy assertion (mex:MetadataExchange).
     The normative outline of this assertion is:
    </p><div class="exampleOuter"><div class="exampleInner"><pre>&lt;mex:MetadataExchange ...&gt;
  &lt;mex:GetMetadataSupported ...&gt;
    &lt;mex:MetadataExchangeDialect Type="<em>mex:QNameSerialization</em>" ...&gt;
      &lt;mex:MetadataContent URI="<em>xs:anyURI</em>" ...&gt;
        <em>xs:any</em>*
      &lt;/mex:MetadataContent&gt; *
      <em>xs:any</em>*
    &lt;/mex:MetadataExchangeDialect&gt; *
    <em>xs:any</em>*
  &lt;/mex:GetMetadataSupported&gt; ?
  &lt;mex:PutMetadataSupported ...&gt;
    &lt;mex:MetadataExchangeDialect Type="<em>mex:QNameSerialization</em>" ...&gt;
      &lt;mex:MetadataContent URI="<em>xs:anyURI</em>" ...&gt;
        <em>xs:any</em>*
      &lt;/mex:MetadataContent&gt; *
      <em>xs:any</em>*
    &lt;/mex:MetadataExchangeDialect&gt; *
    <em>xs:any</em>*
  &lt;/mex:PutMetadataSupported&gt; ?
  &lt;mex:DeleteMetadataSupported ...&gt;
    &lt;mex:MetadataExchangeDialect Type="<em>mex:QNameSerialization</em>" ...&gt;
      &lt;mex:MetadataContent URI="<em>xs:anyURI</em>" ...&gt;
        <em>xs:any</em>*
      &lt;/mex:MetadataContent&gt; *
      <em>xs:any</em>*
    &lt;/mex:MetadataExchangeDialect&gt; *
    <em>xs:any</em>*
  &lt;/mex:DeleteMetadataSupported&gt; ?
  <em>xs:any</em>*
&lt;/mex:MetadataExchange&gt;</pre></div></div><p>
     The following describes additional, normative constraints on the
     outline listed above:
    </p><dl><dt class="label"> /mex:MetadataExchange </dt><dd><p>
         This policy assertion has Endpoint Policy Subject. When present in a
         policy alternative, it indicates that
         the WS-MetadataExchange protocol MUST
         be used when communicating with this endpoint.
        </p></dd><dt class="label"> /mex:MetadataExchange/mex:GetMetadataSupported </dt><dd><p>
         When present, this OPTIONAL parameter indicates that the
         GetMetadata operation is supported by this endpoint.
        </p></dd><dt class="label"> /mex:MetadataExchange/mex:GetMetadataSupported/mex:MetadataExchangeDialect@Type </dt><dd><p>
         When present, this OPTIONAL parameter indicates support for the
         specified MetadataExchange Dialect QName by the GetMetadata operation.
        </p><p>
         Note: the QName is serialized as {namespace-uri}localName.
        </p></dd><dt class="label"> /mex:MetadataExchange/mex:GetMetadataSupported/mex:MetadataExchangeDialect/mex:MetadataContent </dt><dd><p>
         When present, this OPTIONAL parameter indicates support for the
         specified MetadataExchange content IRI by the GetMetadata
         operation for the dialect indicated.
        </p></dd><dt class="label"> /mex:MetadataExchange/mex:GetMetadataSupported/mex:MetadataExchangeDialect/mex:MetadataContent/xs:any </dt><dd><p>
         This extensibility point allows for additional MetadataContent
         specific metadata to be included within the policy assertion. Any
         metadata that appears is scoped to the use of the specified
         MetadataContent URI.
        </p></dd><dt class="label"> /mex:MetadataExchange/mex:GetMetadataSupported/mex:MetadataExchangeDialect/xs:any </dt><dd><p>
         This extensibility point allows for additional Metadata Dialect
         specific metadata to be included within the policy assertion. Any
         metadata that appears is scoped to the use of the specified
         Metadata Dialect QName.
        </p></dd><dt class="label"> /mex:MetadataExchange/mex:GetMetadataSupported/xs:any </dt><dd><p>
         This extensibility point allows for additional metadata specific
         to the GetMetadata operation to be included within the policy
         assertion. Any metadata that appears is scoped to the use of the
         GetMetadata operation.
        </p></dd><dt class="label"> /mex:MetadataExchange/mex:PutMetadataSupported </dt><dd><p>
         When present, this OPTIONAL parameter indicates that the PutMetadata
         operation is supported by this endpoint.
        </p></dd><dt class="label"> /mex:MetadataExchange/mex:PutMetadataSupported/mex:MetadataExchangeDialect@Type </dt><dd><p>
         When present, this OPTIONAL parameter indicates support for the
         specified MetadataExchange Dialect QName by the PutMetadata operation.
        </p><p>
         Note: the QName is serialized as {namespace-uri}localName.
        </p></dd><dt class="label"> /mex:MetadataExchange/mex:PutMetadataSupported/mex:MetadataExchangeDialect/mex:MetadataContent </dt><dd><p>
         When present, this OPTIONAL parameter indicates support for the
         specified MetadataExchange content IRI by the PutMetadata
         operation for the dialect indicated.
        </p></dd><dt class="label"> /mex:MetadataExchange/mex:PutMetadataSupported/mex:MetadataExchangeDialect/mex:MetadataContent/xs:any </dt><dd><p>
         This extensibility point allows for additional MetadataContent
         specific metadata to be included within the policy assertion. Any
         metadata that appears is scoped to the use of the specified
         MetadataContent URI.
        </p></dd><dt class="label"> /mex:MetadataExchange/mex:PutMetadataSupported/mex:MetadataExchangeDialect/xs:any </dt><dd><p>
         This extensibility point allows for additional Metadata Dialect
         specific metadata to be included within the policy assertion. Any
         metadata that appears is scoped to the use of the specified
         Metadata Dialect QName.
        </p></dd><dt class="label"> /mex:MetadataExchange/mex:PutMetadataSupported/xs:any </dt><dd><p>
         This extensibility point allows for additional metadata specific to
         the PutMetadata operation to be included within the policy
         assertion. Any metadata that appears is scoped to the use of the
         PutMetadata operation.
        </p></dd><dt class="label"> /mex:MetadataExchange/mex:DeleteMetadataSupported </dt><dd><p>
         When present, this OPTIONAL parameter indicates that the
         DeleteMetadata operation is supported by this endpoint.
        </p></dd><dt class="label"> /mex:MetadataExchange/mex:DeleteMetadataSupported/mex:MetadataExchangeDialect@Type </dt><dd><p>
         When present, this OPTIONAL parameter indicates support for the
         specified MetadataExchange Dialect QName by the
         DeleteMetadata operation.
        </p><p>
         Note: the QName is serialized as {namespace-uri}localName.
        </p></dd><dt class="label"> /mex:MetadataExchange/mex:DeleteMetadataSupported/mex:MetadataExchangeDialect/mex:MetadataContent </dt><dd><p>
         When present, this OPTIONAL parameter indicates support for the
         specified MetadataExchange content IRI by the DeleteMetadata
         operation for the dialect indicated.
        </p></dd><dt class="label"> /mex:MetadataExchange/mex:DeleteMetadataSupported/mex:MetadataExchangeDialect/mex:MetadataContent/xs:any </dt><dd><p>
         This extensibility point allows for additional MetadataContent
         specific metadata to be included within the policy assertion. Any
         metadata that appears is scoped to the use of the specified
         MetadataContent URI.
        </p></dd><dt class="label"> /mex:MetadataExchange/mex:DeleteMetadataSupported/mex:MetadataExchangeDialect/xs:any </dt><dd><p>
         This extensibility point allows for additional Metadata Dialect
         specific metadata to be included within the policy assertion. Any
         metadata that appears is scoped to the use of the specified
         Metadata Dialect QName.
        </p></dd><dt class="label"> /mex:MetadataExchange/mex:DeleteMetadataSupported/xs:any </dt><dd><p>
         This extensibility point allows for additional metadata specific to
         the DeleteMetadata operation to be included within the policy
         assertion. Any metadata that appears is scoped to the use of the
         DeleteMetadata operation.
        </p></dd><dt class="label"> /mex:MetadataExchange/xs:any </dt><dd><p>
         This extensibility point allows for additional WS-MetadataExchange
         specific metadata to be included within the policy assertion -
         e.g. WS-MetadataExchange WSDL, or nested policy assertions related
         to the WS-MetadataExchange message exchanges. Any metadata that
         appears is scoped to the operations and features of the
         WS-MetadataExchange specification.
        </p></dd></dl></div></div><div class="div1">
<h2><a name="bootstrapping" id="bootstrapping"></a>13 Bootstrapping Metadata Retrieval</h2><p>
    Although the operations described in <a href="#Retrieving-Metadata"><b>6 Retrieving Metadata about Service Endpoints</b></a>
    can be used by a requester to obtain the metadata about a particular
    Service Endpoint, there is the 'chicken and egg' problem of how the
    requester knows whether or not these operations are supported in the first
    place. The facilities described in
    <a href="#Metadata-in-Endpoint-References"><b>8 Metadata in Endpoint References</b></a>,
    <a href="#ImplicitWSDL"><b>9 Exposing Metadata for Implicitly Defined Features</b></a>, and
    <a href="#metadata"><b>12 WS-MetadataExchange Metadata</b></a> can be used to address this problem.
   </p><div class="exampleOuter">
<div class="exampleHeader"><a name="EPRgetwsdl" id="EPRgetwsdl"></a>Example 13-1: Endpoint reference to a Service Endpoint that supports mex:GetWSDL</div><div class="exampleInner"><pre>(01) &lt;wsa:EndpointReference ...&gt;
(02)   &lt;wsa:Address&gt;http://services.example.org/stockquote&lt;/wsa:Address&gt;
(03)   &lt;wsa:Metadata&gt;
(04)     &lt;wsp:Policy&gt;
(05)       &lt;mex:MetadataExchange/&gt;
(06)       &lt;wssa:SOAP11/&gt;
(07)     &lt;/wsp:Policy&gt;
(08)   &lt;/wsa:Metadata&gt;
(09) &lt;/wsa:EndpointReference&gt; </pre></div></div><p>
    The policy assertion at line 05 in <a href="#EPRgetwsdl">Example 13-1</a>
    indicates to consumers of this EPR that the GetWSDL operation is
    supported by the referenced Service Endpoint. The parameters described in
    <a href="#metadata"><b>12 WS-MetadataExchange Metadata</b></a> could be added to the policy assertion at
    line 05 to indicate additional capabilities such as support for the
    mex:GetMetadata operation.
    The assertion on line 06 indicates that SOAP 1.1 needs to be used
    when sending the GetWSDL message.
   </p><p>
    Alternatively the EPR for a Service Endpoint can contain embedded
    metadata or references to Metadata Resources that describe the
    referenced service. <a href="#EPRMEX">Example 8-1</a> illustrated an EPR with
    embedded WSDL metadata. <a href="#WSDLrefinEPR">Example 7-2</a> shows an EPR with a
    reference to a Metadata Resource. The representation of this resource
    (retrievable via HTTP GET) is a WSDL document that describes the
    service at "http://example.com". <a href="#EPRrefMDref">Example 8-3</a> illustrates a
    similar mechanism, except that the retrieval mechanism is WS-Transfer
    and the representation will be a mex:Metadata document.
   </p><p>
    Extra binding information (such as SOAP version) could either be
    implied by the context in which the EPR was provided or could be
    conveyed as in <a href="#EPRwsdl">Example 13-2</a>.
   </p><div class="exampleOuter">
<div class="exampleHeader"><a name="EPRwsdl" id="EPRwsdl"></a>Example 13-2: Endpoint reference to a Service Endpoint that supports mex:GetWSDL</div><div class="exampleInner"><pre>(01) &lt;wsa:EndpointReference ...&gt;
(02)   &lt;wsa:Address&gt;http://services.example.org/stockquote&lt;/wsa:Address&gt;
(03)   &lt;wsa:Metadata&gt;
(04)     &lt;wsp:Policy&gt;
(05)       &lt;mex:MetadataExchange&gt;
{06)         &lt;wsdl:definitions ...&gt;
(07)           &lt;!-- Binding information --&gt;
(08)           &lt;wsdl:binding ...&gt;
(09)             ...
(10)           &lt;/wsdl:binding&gt;
(11)         &lt;/wsdl:definitions&gt;
(12)       &lt;/mex:MetadataExchange&gt;
(13)     &lt;/wsp:Policy&gt;
(14)   &lt;/wsa:Metadata&gt;
(15) &lt;/wsa:EndpointReference&gt; </pre></div></div><p>
    When information about the availability of metadata is not present in
    an EPR, requesters can use contextual or out-of-band information to
    choose the mechanism most appropriate for retrieving the metadata.
    Furthermore, specific mechanisms for metadata retrieval can be defined
    by communities within the context of particular application domains.
   </p></div><div class="div1">
<h2><a name="acks" id="acks"></a>14 Acknowledgements</h2><p>
    This specification has been developed as a result of joint
    work with many individuals and teams, including:
     Alessio Soldano (Red Hat),
     Ashok Malhotra (Oracle Corp.),
     Asir Vedamuthu (Microsoft Corp.),
     Bob Freund (Hitachi, Ltd.),
     Bob Natale (MITRE Corp.),
     David Snelling (Fujitsu, Ltd.),
     Doug Davis (IBM),
     Fred Maciel (Hitachi, Ltd.),
     Geoff Bullen (Microsoft Corp.),
     Gilbert Pilz (Oracle Corp.),
     Greg Carpenter (Microsoft Corp.),
     Jeff Mischkinsky (Oracle Corp.),
     Katy Warr (IBM),
     Li Li (Avaya Communications),
     Mark Little (Red Hat),
     Martin Chapman (Oracle Corp.),
     Paul Fremantle (WSO2),
     Paul Nolan (IBM),
     Prasad Yendluri (Software AG),
     Ram Jeyaraman (Microsoft Corp.),
     Sreedhara Narayanaswamy (CA),
     Sumeet Vij (Software AG),
     Tom Rutt (Fujitsu, Ltd.),
     Vikas Varma (Software AG),
     Wu Chou (Avaya Communications),
     Yves Lafon (W3C/ERCIM).
   </p></div><div class="div1">
<h2><a name="References" id="References"></a>15 References</h2><div class="div2">
<h3><a name="idp1780096" id="idp1780096"></a>15.1 Normative References</h3><dl><dt class="label"><a name="BP12" id="BP12"></a>BP12</dt><dd>
        <a href="http://ws-i.org/profiles/BasicProfile-1.2-2010-11-09.html"><cite>
         WS-I Profile, Basic Profile Version 1.2
        </cite></a>
        , R. Chumbley, et al, Editors.
        Web Services Interoperability Organization (WS-I), 9 November 2010.
      Available at <a href="http://ws-i.org/profiles/BasicProfile-1.2-2010-11-09.html">http://ws-i.org/profiles/BasicProfile-1.2-2010-11-09.html</a>.</dd><dt class="label"><a name="BP20" id="BP20"></a>BP20</dt><dd>
        <a href="http://ws-i.org/profiles/BasicProfile-2.0-2010-11-09.html"><cite>
         WS-I Profile, Basic Profile Version 2.0
        </cite></a>
        , R. Chumbley, et al, Editors.
        Web Services Interoperability Organization (WS-I), 9 November 2010.
      Available at <a href="http://ws-i.org/profiles/BasicProfile-2.0-2010-11-09.html">http://ws-i.org/profiles/BasicProfile-2.0-2010-11-09.html</a>.</dd><dt class="label"><a name="RFC2119" id="RFC2119"></a>RFC 2119</dt><dd>
       <a href="http://www.ietf.org/rfc/rfc2119.txt"><cite>
        Key words for use in RFCs to Indicate Requirement Levels
       </cite></a>
       , S. Bradner, Author.
       Internet Engineering Task Force, March 1997.
      Available at <a href="http://www.ietf.org/rfc/rfc2119.txt">http://www.ietf.org/rfc/rfc2119.txt</a>.</dd><dt class="label"><a name="RFC3987" id="RFC3987"></a>RFC 3987</dt><dd>
       <a href="http://www.ietf.org/rfc/rfc3987.txt"><cite>
        Internationalized Resource Identifiers (IRIs)
       </cite></a>
       , M. Duerst and M. Suignard, Authors.
       Internet Engineering Task Force, January 2005.
      Available at <a href="http://www.ietf.org/rfc/rfc3987.txt">http://www.ietf.org/rfc/rfc3987.txt</a>.</dd><dt class="label"><a name="SOAP11" id="SOAP11"></a>SOAP11</dt><dd>
       <a href="http://www.w3.org/TR/2000/NOTE-SOAP-20000508/"><cite>
        W3C Note, "Simple Object Access Protocol (SOAP) 1.1"
       </cite></a>
       , D. Box, et al, Editors.
       World Wide Web Consortium (W3C), 8 May 2000.
      Available at <a href="http://www.w3.org/TR/2000/NOTE-SOAP-20000508/">http://www.w3.org/TR/2000/NOTE-SOAP-20000508/</a>.</dd><dt class="label"><a name="SOAP12" id="SOAP12"></a>SOAP12</dt><dd>
       <a href="http://www.w3.org/TR/soap12-part1/"><cite>
        W3C Recommendation, "SOAP Version 1.2 Part 1: Messaging Framework"
       </cite></a>
       , M. Gudgin, M. Hadley, N. Mendelsohn, J-J. Moreau, H. Frystyk Nielson,
        Editors.
       World Wide Web Consortium (W3C), 27 April 2007.
      Available at <a href="http://www.w3.org/TR/soap12-part1/">http://www.w3.org/TR/soap12-part1/</a>.</dd><dt class="label"><a name="AddrCore" id="AddrCore"></a>WS-Addressing</dt><dd>
       <a href="http://www.w3.org/TR/ws-addr-core"><cite>
        W3C Recommendation, "Web Services Addressing 1.0 (WS-Addressing)"
       </cite></a>
       , M. Gudgin, M. Hadley, T. Rogers, Editors.
       World Wide Web Consortium (W3C), 9 May 2006.
      Available at <a href="http://www.w3.org/TR/ws-addr-core">http://www.w3.org/TR/ws-addr-core</a>.</dd><dt class="label"><a name="WSABinding" id="WSABinding"></a>WS-Addressing 1.0 SOAP Binding</dt><dd>
       <a href="http://www.w3.org/TR/ws-addr-soap"><cite>
        W3C Recommendation, "Web Services Addressing 1.0 - SOAP Binding"
       </cite></a>
       , M. Gudgin, M. Hadley, T. Rogers, Editors.
       World Wide Web Consortium (W3C), 9 May 2006.
      Available at <a href="http://www.w3.org/TR/ws-addr-soap">http://www.w3.org/TR/ws-addr-soap</a>.</dd><dt class="label"><a name="WS-SOAPAssertions" id="WS-SOAPAssertions"></a>WS-SOAPAssertions</dt><dd>
      <a href="http://www.w3.org/TR/ws-soap-assertions"><cite>
       W3C Working Group Draft, "Web Services SOAP Assertions (WS-SOAPAssertions) 1.0"
      </cite></a>
      , D. Davis, et al., Editors.
      World Wide Web Consortium (W3C), 15 September 2009.
      Available at <a href="http://www.w3.org/TR/ws-soap-assertions">http://www.w3.org/TR/ws-soap-assertions</a>.</dd><dt class="label"><a name="wspolicy" id="wspolicy"></a>WS-Policy</dt><dd>
       <a href="http://www.w3.org/TR/ws-policy/"><cite>
        W3C Recommendation, "Web Services Policy (WS-Policy) 1.5 - Framework"
       </cite></a>
       , A. Vedamuthu, et al., Editors.
       World Wide Web Consortium (W3C), 4 September 2007.
      Available at <a href="http://www.w3.org/TR/ws-policy/">http://www.w3.org/TR/ws-policy/</a>.</dd><dt class="label"><a name="WS-PolicyAttachment" id="WS-PolicyAttachment"></a>WS-PolicyAttachment</dt><dd>
      <a href="http://www.w3.org/TR/ws-policy-attach/"><cite>
       W3C Recommendation, "Web Services Policy (WS-Policy) 1.5 - Attachment"
      </cite></a>
      , A. Vedamuthu, et al., Editors.
      World Wide Web Consortium (W3C), 4 September 2007.
      Available at <a href="http://www.w3.org/TR/ws-policy-attach/">http://www.w3.org/TR/ws-policy-attach/</a>.</dd><dt class="label"><a name="WS-Transfer" id="WS-Transfer"></a>WS-Transfer</dt><dd>
      <a href="http://www.w3.org/TR/ws-transfer"><cite>
       W3C Working Group Draft, "Web Services Transfer (WS-Transfer) 1.1"
      </cite></a>
      , D. Davis, et al., Editors.
      World Wide Web Consortium (W3C), 15 September 2009.
      Available at <a href="http://www.w3.org/TR/ws-transfer">http://www.w3.org/TR/ws-transfer</a>.</dd><dt class="label"><a name="WSDL11" id="WSDL11"></a>WSDL11</dt><dd>
       <a href="http://www.w3.org/TR/2001/NOTE-wsdl-20010315"><cite>
        W3C Note, "Web Services Description Language (WSDL) 1.1"
       </cite></a>
       , E. Christensen, et al., Editors.
       World Wide Web Consortium (W3C), 15 March 2001
      Available at <a href="http://www.w3.org/TR/2001/NOTE-wsdl-20010315">http://www.w3.org/TR/2001/NOTE-wsdl-20010315</a>.</dd><dt class="label"><a name="XMLInfoset" id="XMLInfoset"></a>XML Infoset</dt><dd>
       <a href="http://www.w3.org/TR/xml-infoset"><cite>
        W3C Recommendation, "XML Information Set (Second Edition)"
       </cite></a>
       , J. Cowan, R. Tobin, Editors.
       World Wide Web Consortium (W3C), 4 February 2004.
      Available at <a href="http://www.w3.org/TR/xml-infoset">http://www.w3.org/TR/xml-infoset</a>.</dd><dt class="label"><a name="XMLSchema1" id="XMLSchema1"></a>XMLSchema - Part 1</dt><dd>
       <a href="http://www.w3.org/TR/xmlschema-1/"><cite>
        W3C Recommendation, "XML Schema Part 1: Structures (Second Edition)"
       </cite></a>
       , H. Thompson, et al., Editors.
       World Wide Web Consortium (W3C), 28 October 2004.
      Available at <a href="http://www.w3.org/TR/xmlschema-1/">http://www.w3.org/TR/xmlschema-1/</a>.</dd><dt class="label"><a name="XMLSchema2" id="XMLSchema2"></a>XMLSchema - Part 2</dt><dd>
       <a href="http://www.w3.org/TR/xmlschema-2/"><cite>
        W3C Recommendation, "XML Schema Part 2: Datatypes (Second Edition)"
       </cite></a>
       , P. Biron, A. Malhotra, Editors.
       World Wide Web Consortium (W3C), 28 October 2004.
      Available at <a href="http://www.w3.org/TR/xmlschema-2/">http://www.w3.org/TR/xmlschema-2/</a>.</dd></dl></div></div></div><div class="back"><div class="div1">
<h2><a name="Appendix-A" id="Appendix-A"></a>A XML Schema</h2><p>
    A normative copy of the XML Schema <a href="#XMLSchema1">[XMLSchema - Part 1]</a>,
    <a href="#XMLSchema2">[XMLSchema - Part 2]</a> description for this specification can be
    retrieved from the following address:
   </p><div class="exampleOuter"><div class="exampleInner"><pre><a href="http://www.w3.org/2011/03/ws-mex/MetadataExchange.xsd">http://www.w3.org/2011/03/ws-mex/MetadataExchange.xsd</a></pre></div></div><p>
    A non-normative copy of the XML schema is listed below for convenience.
   </p><div class="exampleOuter"><div class="exampleInner"><pre>&lt;xs:schema
    targetNamespace='http://www.w3.org/2011/03/ws-mex'
    xmlns:tns='http://www.w3.org/2011/03/ws-mex'
    xmlns:wsa='http://www.w3.org/2005/08/addressing'
    xmlns:xs='http://www.w3.org/2001/XMLSchema'
    elementFormDefault='qualified'
    blockDefault='#all'&gt;

  &lt;xs:import
      namespace='http://www.w3.org/2005/08/addressing'
      schemaLocation='http://www.w3.org/2006/03/addressing/ws-addr.xsd'/&gt;


  &lt;xs:simpleType name='QNameSerialization'&gt;
    &lt;xs:restriction base='xs:string'&gt;
      &lt;xs:pattern value='\{.*\}.+'/&gt;

    &lt;/xs:restriction&gt;
  &lt;/xs:simpleType&gt;

  &lt;!-- GetWSDL request --&gt;
  &lt;xs:element name='GetWSDL'&gt;
    &lt;xs:complexType&gt;
      &lt;xs:sequence&gt;
        &lt;xs:any namespace='##other' processContents='lax' minOccurs='0'
                maxOccurs='unbounded'/&gt;
      &lt;/xs:sequence&gt;
      &lt;xs:anyAttribute namespace='##other' processContents='lax'/&gt;
    &lt;/xs:complexType&gt;
  &lt;/xs:element&gt;

  &lt;!-- GetWSDL response --&gt;
  &lt;xs:element name='GetWSDLResponse'&gt;
    &lt;xs:complexType&gt;
      &lt;xs:sequence&gt;
        &lt;xs:any namespace='##other' processContents='lax' minOccurs='0'
                maxOccurs='unbounded'/&gt;
      &lt;/xs:sequence&gt;
      &lt;xs:anyAttribute namespace='##other' processContents='lax'/&gt;
    &lt;/xs:complexType&gt;
  &lt;/xs:element&gt;

  &lt;!-- Get Metadata request --&gt;
  &lt;xs:element name='GetMetadata'&gt;
    &lt;xs:complexType&gt;
      &lt;xs:sequence&gt;
        &lt;xs:element ref='tns:Dialect' minOccurs='0' maxOccurs='unbounded'/&gt;
        &lt;xs:any namespace='##other' processContents='lax' minOccurs='0'
                maxOccurs='unbounded'/&gt;
      &lt;/xs:sequence&gt;
      &lt;xs:attribute name='Content' type='xs:anyURI'/&gt;
      &lt;xs:anyAttribute namespace='##other' processContents='lax'/&gt;
    &lt;/xs:complexType&gt;
  &lt;/xs:element&gt;

  &lt;!-- Get Metadata response --&gt;
  &lt;xs:element name='GetMetadataResponse'&gt;
    &lt;xs:complexType&gt;
      &lt;xs:sequence&gt;
        &lt;xs:element ref='tns:Metadata'/&gt;
        &lt;xs:any namespace='##other' processContents='lax' minOccurs='0'
                maxOccurs='unbounded'/&gt;
      &lt;/xs:sequence&gt;
      &lt;xs:anyAttribute namespace='##other' processContents='lax'/&gt;
    &lt;/xs:complexType&gt;
  &lt;/xs:element&gt;

  &lt;!-- Put Metadata request --&gt;
  &lt;xs:element name='PutMetadata'&gt;
    &lt;xs:complexType&gt;
      &lt;xs:sequence&gt;
        &lt;xs:element ref='tns:Metadata'/&gt;
        &lt;xs:any namespace='##other' processContents='lax' minOccurs='0'
                maxOccurs='unbounded'/&gt;
      &lt;/xs:sequence&gt;
      &lt;xs:anyAttribute namespace='##other' processContents='lax'/&gt;
    &lt;/xs:complexType&gt;
  &lt;/xs:element&gt;

  &lt;!-- Put Metadata response --&gt;
  &lt;xs:element name='PutMetadataResponse'&gt;
    &lt;xs:complexType&gt;
      &lt;xs:sequence&gt;
        &lt;xs:element ref='tns:Metadata' minOccurs='0'/&gt;
        &lt;xs:any namespace='##other' processContents='lax' minOccurs='0'
                maxOccurs='unbounded'/&gt;
      &lt;/xs:sequence&gt;
      &lt;xs:anyAttribute namespace='##other' processContents='lax'/&gt;
    &lt;/xs:complexType&gt;
  &lt;/xs:element&gt;

  &lt;!-- Delete Metadata request --&gt;
  &lt;xs:element name='DeleteMetadata'&gt;
    &lt;xs:complexType&gt;
      &lt;xs:sequence&gt;
        &lt;xs:element ref='tns:Dialect' minOccurs='0' maxOccurs='unbounded'/&gt;
        &lt;xs:any namespace='##other' processContents='lax' minOccurs='0'
                maxOccurs='unbounded'/&gt;
      &lt;/xs:sequence&gt;
      &lt;xs:anyAttribute namespace='##other' processContents='lax'/&gt;
    &lt;/xs:complexType&gt;
  &lt;/xs:element&gt;

  &lt;!-- Delete Metadata response --&gt;
  &lt;xs:element name='DeleteMetadataResponse'&gt;
    &lt;xs:complexType&gt;
      &lt;xs:sequence&gt;
        &lt;xs:any namespace='##other' processContents='lax' minOccurs='0'
                maxOccurs='unbounded'/&gt;
      &lt;/xs:sequence&gt;
      &lt;xs:anyAttribute namespace='##other' processContents='lax'/&gt;
    &lt;/xs:complexType&gt;
  &lt;/xs:element&gt;

  &lt;xs:element name='Dialect'&gt;
    &lt;xs:complexType&gt;
      &lt;xs:attribute name='Type' type='tns:QNameSerialization' use='required'/&gt;
      &lt;xs:attribute name='Identifier' type='xs:anyURI'/&gt;
      &lt;xs:attribute name='Content' type='xs:anyURI'/&gt;
      &lt;xs:anyAttribute namespace='##other' processContents='lax'/&gt;
    &lt;/xs:complexType&gt;
  &lt;/xs:element&gt;

  &lt;!-- Metadata --&gt;
  &lt;xs:element name='Metadata'&gt;
    &lt;xs:complexType&gt;
      &lt;xs:sequence&gt;
        &lt;xs:element ref='tns:MetadataSection'
                    minOccurs='0'
                    maxOccurs='unbounded'/&gt;
        &lt;xs:any namespace='##other' processContents='lax'
                minOccurs='0'
                maxOccurs='unbounded'/&gt;
      &lt;/xs:sequence&gt;
      &lt;xs:anyAttribute namespace='##other' processContents='lax'/&gt;
    &lt;/xs:complexType&gt;
  &lt;/xs:element&gt;

  &lt;xs:element name='MetadataSection'&gt;
    &lt;xs:complexType&gt;
      &lt;xs:choice&gt;
        &lt;xs:any namespace='##other' processContents='lax'/&gt;
        &lt;xs:element name='MetadataReference' type='wsa:EndpointReferenceType' /&gt;
        &lt;xs:element name='MetadataLocation' type='tns:URI'/&gt;
      &lt;/xs:choice&gt;
      &lt;xs:attribute name='Dialect' type='tns:QNameSerialization' use='required'/&gt;
      &lt;xs:attribute name='Identifier' type='xs:anyURI' use='required'/&gt;
      &lt;xs:anyAttribute namespace='##other' processContents='lax'/&gt;
    &lt;/xs:complexType&gt;
  &lt;/xs:element&gt;

  &lt;xs:complexType name='LocationType'&gt;
    &lt;xs:sequence&gt;
      &lt;xs:any namespace='##other' processContents='lax' minOccurs='0'
              maxOccurs='unbounded'/&gt;
    &lt;/xs:sequence&gt;
    &lt;xs:attribute name='URL'  type='xs:anyURI' use='required'/&gt;
    &lt;xs:attribute name='Type' type='tns:QNameSerialization'  use='required'/&gt;
    &lt;xs:attribute name='Identifier' type='xs:anyURI' use='required'/&gt;
    &lt;xs:anyAttribute namespace='##other' processContents='lax'/&gt;
  &lt;/xs:complexType&gt;
  &lt;xs:element name='Location' type='tns:LocationType'/&gt;

  &lt;xs:complexType name='ReferenceType'&gt;
    &lt;xs:complexContent&gt;
      &lt;xs:extension base='wsa:EndpointReferenceType'&gt;
        &lt;xs:attribute name='Type' type='tns:QNameSerialization'  use='required'/&gt;
        &lt;xs:attribute name='Identifier' type='xs:anyURI' use='required'/&gt;
        &lt;xs:anyAttribute processContents='lax'/&gt;
      &lt;/xs:extension&gt;
    &lt;/xs:complexContent&gt;
  &lt;/xs:complexType&gt;
  &lt;xs:element name='Reference' type='tns:ReferenceType'/&gt;

  &lt;!-- Policy --&gt;
  &lt;xs:complexType name='URI'&gt;
    &lt;xs:simpleContent&gt;
      &lt;xs:extension base='xs:anyURI'&gt;
        &lt;xs:anyAttribute namespace='##other' processContents='lax'/&gt;
      &lt;/xs:extension&gt;
    &lt;/xs:simpleContent&gt;
  &lt;/xs:complexType&gt;

  &lt;xs:element name='MetadataExchange'&gt;
    &lt;xs:complexType&gt;
      &lt;xs:sequence&gt;
        &lt;xs:element name='GetMetadataSupported' minOccurs='0'&gt;
          &lt;xs:complexType&gt;
            &lt;xs:sequence&gt;
              &lt;xs:element name='MetadataExchangeDialect'
                          minOccurs='0' maxOccurs='unbounded'&gt;
                &lt;xs:complexType&gt;
                  &lt;xs:sequence&gt;
                    &lt;xs:element name='MetadataContent'
                                minOccurs='0' maxOccurs='unbounded'&gt;
                      &lt;xs:complexType&gt;
                        &lt;xs:sequence&gt;
                          &lt;xs:any namespace='##other' processContents='lax'
                                  minOccurs='0' maxOccurs='0'/&gt;
                        &lt;/xs:sequence&gt;
                        &lt;xs:attribute name='URI' type='xs:anyURI'
                                                 use='required' /&gt;
                        &lt;xs:anyAttribute namespace="##other"
                                         processContents='lax'/&gt;
                      &lt;/xs:complexType&gt;
                    &lt;/xs:element&gt;
                    &lt;xs:any namespace='##other' processContents='lax'
                            minOccurs='0' maxOccurs='unbounded'/&gt;
                  &lt;/xs:sequence&gt;
                  &lt;xs:attribute name='URI' type='xs:anyURI'
                                use='required'/&gt;
                  &lt;xs:anyAttribute namespace='##other'
                                   processContents='lax'/&gt;
                &lt;/xs:complexType&gt;
              &lt;/xs:element&gt;
              &lt;xs:any namespace='##other' processContents='lax'
                      minOccurs='0' maxOccurs='unbounded'/&gt;
            &lt;/xs:sequence&gt;
            &lt;xs:anyAttribute namespace='##other' processContents='lax' /&gt;
          &lt;/xs:complexType&gt;
        &lt;/xs:element&gt;
        &lt;xs:element name='PutMetadataSupported' minOccurs='0'&gt;
          &lt;xs:complexType&gt;
            &lt;xs:sequence&gt;
              &lt;xs:element name='MetadataExchangeDialect'
                          minOccurs='0' maxOccurs='unbounded'&gt;
                &lt;xs:complexType&gt;
                  &lt;xs:sequence&gt;
                    &lt;xs:element name='MetadataContent'
                                minOccurs='0' maxOccurs='unbounded'&gt;
                      &lt;xs:complexType&gt;
                        &lt;xs:sequence&gt;
                          &lt;xs:any namespace='##other' processContents='lax'
                                  minOccurs='0' maxOccurs='0'/&gt;
                        &lt;/xs:sequence&gt;
                        &lt;xs:attribute name='URI' type='xs:anyURI'
                                                 use='required' /&gt;
                        &lt;xs:anyAttribute namespace="##other"
                                         processContents='lax'/&gt;
                      &lt;/xs:complexType&gt;
                    &lt;/xs:element&gt;
                    &lt;xs:any namespace='##other' processContents='lax'
                            minOccurs='0' maxOccurs='unbounded'/&gt;
                  &lt;/xs:sequence&gt;
                  &lt;xs:attribute name='URI' type='xs:anyURI'
                                use='required'/&gt;
                  &lt;xs:anyAttribute namespace='##other'
                                   processContents='lax'/&gt;
                &lt;/xs:complexType&gt;
              &lt;/xs:element&gt;
              &lt;xs:any namespace='##other' processContents='lax'
                      minOccurs='0' maxOccurs='unbounded'/&gt;
            &lt;/xs:sequence&gt;
            &lt;xs:anyAttribute namespace='##other' processContents='lax' /&gt;
          &lt;/xs:complexType&gt;
        &lt;/xs:element&gt;
        &lt;xs:element name='DeleteMetadataSupported' minOccurs='0'&gt;
          &lt;xs:complexType&gt;
            &lt;xs:sequence&gt;
              &lt;xs:element name='MetadataExchangeDialect'
                          minOccurs='0' maxOccurs='unbounded'&gt;
                &lt;xs:complexType&gt;
                  &lt;xs:sequence&gt;
                    &lt;xs:element name='MetadataContent'
                                minOccurs='0' maxOccurs='unbounded'&gt;
                      &lt;xs:complexType&gt;
                        &lt;xs:sequence&gt;
                          &lt;xs:any namespace='##other' processContents='lax'
                                  minOccurs='0' maxOccurs='0'/&gt;
                        &lt;/xs:sequence&gt;
                        &lt;xs:attribute name='URI' type='xs:anyURI'
                                                 use='required' /&gt;
                        &lt;xs:anyAttribute namespace="##other"
                                         processContents='lax'/&gt;
                      &lt;/xs:complexType&gt;
                    &lt;/xs:element&gt;
                    &lt;xs:any namespace='##other' processContents='lax'
                            minOccurs='0' maxOccurs='unbounded'/&gt;
                  &lt;/xs:sequence&gt;
                  &lt;xs:attribute name='URI' type='xs:anyURI'
                                use='required'/&gt;
                  &lt;xs:anyAttribute namespace='##other'
                                   processContents='lax'/&gt;
                &lt;/xs:complexType&gt;
              &lt;/xs:element&gt;
              &lt;xs:any namespace='##other' processContents='lax'
                      minOccurs='0' maxOccurs='unbounded'/&gt;
            &lt;/xs:sequence&gt;
            &lt;xs:anyAttribute namespace='##other' processContents='lax' /&gt;
          &lt;/xs:complexType&gt;
        &lt;/xs:element&gt;
      &lt;/xs:sequence&gt;
    &lt;/xs:complexType&gt;
  &lt;/xs:element&gt;

&lt;/xs:schema&gt;</pre></div></div></div><div class="div1">
<h2><a name="Appendix-B" id="Appendix-B"></a>B WSDL</h2><p>
    A normative copy of the WSDL <a href="#WSDL11">[WSDL11]</a> description for
    this specification can be retrieved from the following address:
   </p><div class="exampleOuter"><div class="exampleInner"><pre><a href="http://www.w3.org/2011/03/ws-mex/metadataexchange.wsdl">http://www.w3.org/2011/03/ws-mex/metadataexchange.wsdl</a></pre></div></div><p>
    A non-normative copy of the WSDL description is listed below for
    convenience.
   </p><div class="exampleOuter"><div class="exampleInner"><pre>&lt;wsdl:definitions
    targetNamespace='http://www.w3.org/2011/03/ws-mex'
    xmlns:tns='http://www.w3.org/2011/03/ws-mex'
    xmlns:wsa='http://www.w3.org/2005/08/addressing'
    xmlns:wsam='http://www.w3.org/2007/05/addressing/metadata'
    xmlns:wsdl='http://schemas.xmlsoap.org/wsdl/'
    xmlns:xs='http://www.w3.org/2001/XMLSchema' &gt;

  &lt;wsdl:types&gt;
    &lt;xs:schema
        targetNamespace='http://www.w3.org/2011/03/ws-mex' &gt;
      &lt;xs:include schemaLocation='metadataexchange.xsd' /&gt;
    &lt;/xs:schema&gt;
  &lt;/wsdl:types&gt;

  &lt;wsdl:message name='GetWSDLMsg'&gt;
    &lt;wsdl:part name='body' element='tns:GetWSDL'/&gt;
  &lt;/wsdl:message&gt;

  &lt;wsdl:message name='GetWSDLResponseMsg'&gt;
    &lt;wsdl:part name='body' element='tns:GetWSDLResponse'/&gt;
  &lt;/wsdl:message&gt;

  &lt;wsdl:message name='GetMetadataMsg' &gt;
    &lt;wsdl:part name='body' element='tns:GetMetadata' /&gt;
  &lt;/wsdl:message&gt;
  &lt;wsdl:message name='GetMetadataResponseMsg' &gt;
    &lt;wsdl:part name='body' element='tns:GetMetadataResponse' /&gt;
  &lt;/wsdl:message&gt;

  &lt;wsdl:message name='PutMetadataMsg' &gt;
    &lt;wsdl:part name='body' element='tns:PutMetadata' /&gt;
  &lt;/wsdl:message&gt;
  &lt;wsdl:message name='PutMetadataResponseMsg' &gt;
    &lt;wsdl:part name='body' element='tns:PutMetadataResponse' /&gt;
  &lt;/wsdl:message&gt;

  &lt;wsdl:message name='DeleteMetadataMsg' &gt;
    &lt;wsdl:part name='body' element='tns:DeleteMetadata' /&gt;
  &lt;/wsdl:message&gt;
  &lt;wsdl:message name='DeleteMetadataResponseMsg' &gt;
    &lt;wsdl:part name='body' element='tns:DeleteMetadataResponse' /&gt;
  &lt;/wsdl:message&gt;

  &lt;wsdl:portType name='MetadataExchange' &gt;

    &lt;wsdl:operation name='GetWSDL'&gt;
      &lt;wsdl:input
       message='tns:GetWSDLMsg'
       wsam:Action=
        'http://www.w3.org/2011/03/ws-mex/GetWSDL'/&gt;
      &lt;wsdl:output
       message='tns:GetWSDLResponseMsg'
       wsam:Action=
        'http://www.w3.org/2011/03/ws-mex/GetWSDLResponse'/&gt;
    &lt;/wsdl:operation&gt;

    &lt;wsdl:operation name='GetMetadata' &gt;
      &lt;wsdl:input
       message='tns:GetMetadataMsg'
       wsam:Action=
        'http://www.w3.org/2011/03/ws-mex/GetMetadata'/&gt;
      &lt;wsdl:output
       message='tns:GetMetadataResponseMsg'
       wsam:Action=
        'http://www.w3.org/2011/03/ws-mex/GetMetadataResponse'/&gt;
    &lt;/wsdl:operation&gt;

    &lt;wsdl:operation name='PutMetadata' &gt;
      &lt;wsdl:input
       message='tns:PutMetadataMsg'
       wsam:Action=
        'http://www.w3.org/2011/03/ws-mex/PutMetadata'/&gt;
      &lt;wsdl:output
       message='tns:PutMetadataResponseMsg'
       wsam:Action=
        'http://www.w3.org/2011/03/ws-mex/PutMetadataResponse'/&gt;
    &lt;/wsdl:operation&gt;

    &lt;wsdl:operation name='DeleteMetadata' &gt;
      &lt;wsdl:input
       message='tns:DeleteMetadataMsg'
       wsam:Action=
        'http://www.w3.org/2011/03/ws-mex/DeleteMetadata'/&gt;
      &lt;wsdl:output
       message='tns:DeleteMetadataResponseMsg'
       wsam:Action=
        'http://www.w3.org/2011/03/ws-mex/DeleteMetadataResponse'/&gt;
    &lt;/wsdl:operation&gt;

  &lt;/wsdl:portType&gt;

&lt;/wsdl:definitions&gt;</pre></div></div></div><div class="div1">
<h2><a name="changelog" id="changelog"></a>C Change Log</h2><table border="1"><tbody><tr><th> Data </th><th> Author </th><th> Description </th></tr><tr><td> 2009/03/04 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=6391">6391</a>
      </td></tr><tr><td> 2009/03/04 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=6519">6519</a>
      </td></tr><tr><td> 2009/03/04 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=6442">6442</a>
      </td></tr><tr><td> 2009/03/11 </td><td> DD </td><td> Added change log </td></tr><tr><td> 2009/03/11 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=6639">6639</a>
      </td></tr><tr><td> 2009/03/11 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=6425">6425</a>
      </td></tr><tr><td> 2009/03/16 </td><td> KW </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=6587">6587</a>
      </td></tr><tr><td> 2009/03/17 </td><td> KW </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=6405">6405</a>
      </td></tr><tr><td> 2009/03/17 </td><td> KW </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=6604">6604</a>
      </td></tr><tr><td> 2009/03/18 </td><td> AM </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=6404">6404</a>
      </td></tr><tr><td> 2009/03/23 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=6666">6666</a>
      </td></tr><tr><td> 2009/03/24 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=6648">6648</a>
      </td></tr><tr><td> 2009/04/07 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=6728">6728</a>
      </td></tr><tr><td> 2009/04/22 </td><td> KW </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=6739">6739</a>
      </td></tr><tr><td> 2009/04/28 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=6787">6787</a>
      </td></tr><tr><td> 2009/05/12 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=6433">6433</a>
      </td></tr><tr><td> 2009/05/21 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=6674">6674</a>
      </td></tr><tr><td> 2009/05/27 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=6906">6906</a>
      </td></tr><tr><td> 2009/07/21 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=7122">7122</a>
      </td></tr><tr><td> 2009/07/21 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=6500">6500</a>
      </td></tr><tr><td> 2009/08/04 </td><td> DD </td><td> Added resolution of issues
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=6719">6719</a>,
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=6720">6720</a>
      </td></tr><tr><td> 2009/08/06 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=7194">7194</a>
      </td></tr><tr><td> 2009/08/06 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=6679">6679</a>
      </td></tr><tr><td> 2009/08/18 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=7206">7206</a>
      </td></tr><tr><td> 2009/08/18 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=7195">7195</a>
      </td></tr><tr><td> 2009/08/25 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=7365">7365</a>
      </td></tr><tr><td> 2009/08/25 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=7270">7270</a>
      </td></tr><tr><td> 2009/09/01 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=6702">6702</a>
      </td></tr><tr><td> 2009/09/02 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=6694">6694</a>
      </td></tr><tr><td> 2009/09/02 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=6533">6533</a>
      </td></tr><tr><td> 2009/09/23 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=6570">6570</a>
      </td></tr><tr><td> 2009/10/02 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=7426">7426</a>
      </td></tr><tr><td> 2009/10/05 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=6406">6406</a>,
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=6721">6721</a>
      </td></tr><tr><td> 2009/10/13 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=7827">7827</a>
      </td></tr><tr><td> 2009/10/20 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=7068">7068</a>
      </td></tr><tr><td> 2009/10/20 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=7207">7207</a>
      </td></tr><tr><td> 2009/11/05 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=7912">7912</a>
      </td></tr><tr><td> 2009/11/06 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=8204">8204</a>
      </td></tr><tr><td> 2009/11/06 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=8168">8168</a>
      </td></tr><tr><td> 2009/11/06 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=8199">8199</a>
      </td></tr><tr><td> 2009/11/06 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=8214">8214</a>
      </td></tr><tr><td> 2009/11/06 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=8124">8124</a>
      </td></tr><tr><td> 2009/11/17 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=8280">8280</a>
      </td></tr><tr><td> 2009/12/01 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=8291">8291</a>
      </td></tr><tr><td> 2009/12/01 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=8203">8203</a>
      </td></tr><tr><td> 2009/12/01 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=8201">8201</a>
      </td></tr><tr><td> 2009/12/08 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=8227">8227</a>
      </td></tr><tr><td> 2009/12/15 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=8200">8200</a>
      </td></tr><tr><td> 2009/12/15 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=8297">8297</a>
      </td></tr><tr><td> 2009/12/15 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=8202">8202</a>
      </td></tr><tr><td> 2010/01/12 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=8293">8293</a>
      </td></tr><tr><td> 2010/01/27 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=8294">8294</a>
      </td></tr><tr><td> 2010/01/27 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=8292">8292</a>
      </td></tr><tr><td> 2010/01/27 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=8290">8290</a>
      </td></tr><tr><td> 2010/01/27 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=8205">8205</a>
      </td></tr><tr><td> 2010/01/28 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=7728">7728</a>
      </td></tr><tr><td> 2010/02/09 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=8160">8160</a>
      </td></tr><tr><td> 2010/03/09 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=6463">6463</a>,
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=8031">8031</a>,
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=8198">8198</a>
      </td></tr><tr><td> 2010/03/16 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=8289">8289</a>
      </td></tr><tr><td> 2010/03/30 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=9031">9031</a>
      </td></tr><tr><td> 2010/03/30 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=9266">9266</a>
      </td></tr><tr><td> 2010/04/20 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=9250">9250</a>
      </td></tr><tr><td> 2010/05/04 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=9087">9087</a>
      </td></tr><tr><td> 2010/05/11 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=9570">9570</a>
      </td></tr><tr><td> 2010/05/11 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=9699">9699</a>
      </td></tr><tr><td> 2010/05/11 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=9671">9671</a>
      </td></tr><tr><td> 2010/05/12 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=9709">9709</a>
      </td></tr><tr><td> 2010/08/17 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=10339">10339</a>
      </td></tr><tr><td> 2010/09/28 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=10768">10768</a>
      </td></tr><tr><td> 2010/09/28 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=10785">10785</a>
      </td></tr><tr><td> 2010/11/19 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=8284">8284</a>
      </td></tr><tr><td> 2010/12/14 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=11189">11189</a>
      </td></tr><tr><td> 2011/01/26 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=11625">11625</a>
      </td></tr><tr><td> 2011/01/26 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=11849">11849</a>
      </td></tr><tr><td> 2011/01/26 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=11867">11867</a>
      </td></tr><tr><td> 2011/02/01 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=11850">11850</a>
      </td></tr><tr><td> 2011/02/01 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=11882">11882</a>
      </td></tr><tr><td> 2011/02/07 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=11899">11899</a>
      </td></tr><tr><td> 2011/02/15 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=11865">11865</a>
      </td></tr><tr><td> 2011/02/17 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=12113">12113</a>
      </td></tr><tr><td> 2011/02/17 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=11790">11790</a>
      </td></tr><tr><td> 2011/03/22 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=12093">12093</a>
      </td></tr><tr><td> 2011/04/19 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=12457">12457</a>
      </td></tr><tr><td> 2011/07/05 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=13148">13148</a>
      </td></tr><tr><td> 2011/07/05 </td><td> DD </td><td> Added resolution of issue
       <a href="http://www.w3.org/Bugs/Public/show_bug.cgi?id=13151">13151</a>
      </td></tr></tbody></table></div></div></body></html>