WD-xhtml-forms-req-20010404 34.9 KB
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<h1>XForms Requirements </h1>
<h2>W3C Working Draft 04 April 2001</h2><dl><dt>This version:</dt><dd>
      <a href="http://www.w3.org/TR/2001/WD-xhtml-forms-req-20010404">http://www.w3.org/TR/2001/WD-xhtml-forms-req-20010404</a>      
    </dd><dt>Latest version:</dt><dd> 
      <a href="http://www.w3.org/TR/xhtml-forms-req">
        http://www.w3.org/TR/xhtml-forms-req</a> 
    </dd><dt>Previous versions:</dt><dd> 
      <a href="http://www.w3.org/TR/2000/WD-xhtml-forms-req-20000821">
        http://www.w3.org/TR/2000/WD-xhtml-forms-req-20000821</a> 
    </dd><dt>Editors:</dt> 
      <dd>Micah Dubinko, Cardiff <a href="mailto:mdubinko@Cardiff.com">&lt;mdubinko@Cardiff.com&gt;</a></dd> 
      <dd>Sebastian Schnitzenbaumer, Mozquito Technologies <a href="mailto:schnitz@mozquito.com">&lt;schintz@mozquito.com&gt;</a></dd> 
      <dd>Malte Wedel, Mozquito Technologies <a href="mailto:malte@mozquito.com">&lt;malte@mozquito.com&gt;</a></dd> 
      <dd>Dave Raggett, W3C <a href="mailto:dsr@w3.org">&lt;dsr@w3.org&gt;</a></dd> 
    </dl><p class="copyright"><a href="http://www.w3.org/Consortium/Legal/ipr-notice-20000612#Copyright"> Copyright</a> &copy;2001 <a href="http://www.w3.org/"><abbr title="World Wide Web Consortium">W3C</abbr></a><sup>&reg;</sup> (<a href="http://www.lcs.mit.edu/"><abbr title="Massachusetts Institute of Technology">MIT</abbr></a>, <a href="http://www.inria.fr/"><abbr lang="fr" title="Institut National de Recherche en Informatique et Automatique">INRIA</abbr></a>, <a href="http://www.keio.ac.jp/">Keio</a>), All Rights Reserved. W3C <a href="http://www.w3.org/Consortium/Legal/ipr-notice-20000612#Legal_Disclaimer">liability</a>, <a href="http://www.w3.org/Consortium/Legal/ipr-notice-20000612#W3C_Trademarks">trademark</a>, <a href="http://www.w3.org/Consortium/Legal/copyright-documents-19990405">document use</a> and <a href="http://www.w3.org/Consortium/Legal/copyright-software-19980720">software licensing</a> rules apply.</p></div><hr><div>
<h2><a name="abstract">Abstract</a></h2> 
      <p> Forms were introduced into HTML in 1993. Since then they have gone on
        to become a critical part of the Web. The existing mechanisms in HTML for forms
        are now outdated, and W3C has started work on developing an effective
        replacement. This document outlines the requirements for "XForms", W3C's name
         for the next generation of Web forms.</p> 
    </div><div>
<h2><a name="status">Status of this Document</a></h2> 
      <p><em>This section describes the status of this document at the time
        of its publication. Other documents may supersede this document. The latest
        status of this document series is maintained at the W3C.</em></p> 
      <p>This requirements document incorporates changes made at the recent meeting of the XForms Working Group. This document is a W3C Working Draft for review by W3C members and
        other interested parties. It is a draft document and may be updated, replaced,
        or obsoleted by other documents at any time. It is inappropriate to use W3C
        Working Drafts as reference material or to cite them as other than "work in
        progress". A list of current public W3C Working Drafts can be found at 
        <a href="http://www.w3.org/TR/">http://www.w3.org/TR</a>.</p> 
      <p>This specification describes requirements for the next generation of
        Web forms. This document has been produced as part of the 
        <a href="http://www.w3.org/MarkUp/Forms">W3C work on XForms</a>,
        following the procedures set out for the 
        <a href="http://www.w3.org/Consortium/Process">W3C Process</a>. The
        authors of this document are members of the 
        <a href="http://www.w3.org/MarkUp/Forms/Group/"> W3C XForms working
          group</a> (W3C Members only). This document is for public review, and
        comments and discussion are welcomed on the public mailing list &lt;<a href="mailto:www-forms@w3.org">www-forms@w3.org</a>&gt;. To
        subscribe, send an email to &lt;<a href="mailto:www-forms-request@w3.org">www-forms-request@w3.org</a>&gt; with
        the word <em>subscribe</em> in the subject line (include the word
        <em>unsubscribe</em> if you want to unsubscribe). The 
        <a href="http://lists.w3.org/Archives/Public/www-forms/">archive</a> for the
        list is accessible online.</p> 
    </div> 
  <div class="toc">
<h2><a name="contents">Table of Contents</a></h2><p class="toc">1 <a href="#reqintro">Introduction (Non-Normative)</a><br>&nbsp;&nbsp;&nbsp;&nbsp;1.1 <a href="#reqintro-rationale">Rationale</a><br>&nbsp;&nbsp;&nbsp;&nbsp;1.2 <a href="#reqintro-audience">Target Audience</a><br>2 <a href="#charter-req">Charter and Basic Requirements (Normative)</a><br>&nbsp;&nbsp;&nbsp;&nbsp;2.1 <a href="#in-xml">Defined in XML, Usable in XML</a><br>&nbsp;&nbsp;&nbsp;&nbsp;2.2 <a href="#w3c-integration">W3C Integration</a><br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;2.2.1 <a href="#w3c-integration-p3p">P3P</a><br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;2.2.2 <a href="#w3c-integration-schema">XML Schema</a><br>&nbsp;&nbsp;&nbsp;&nbsp;2.3 <a href="#from-html4">Migration from HTML 4</a><br>&nbsp;&nbsp;&nbsp;&nbsp;2.4 <a href="#ease-of-authoring">Ease of Authoring</a><br>&nbsp;&nbsp;&nbsp;&nbsp;2.5 <a href="#separate-p-from-p">Separate Purpose from Presentation</a><br>&nbsp;&nbsp;&nbsp;&nbsp;2.6 <a href="#device-independence">Device Independence</a><br>&nbsp;&nbsp;&nbsp;&nbsp;2.7 <a href="#scripting-interfaces">Scripting Interfaces</a><br>&nbsp;&nbsp;&nbsp;&nbsp;2.8 <a href="#unicode-i18n">Unicode and Internationalization</a><br>3 <a href="#model-req">XForms Model Requirements (Normative)</a><br>&nbsp;&nbsp;&nbsp;&nbsp;3.1 <a href="#datatypes">Data Types</a><br>&nbsp;&nbsp;&nbsp;&nbsp;3.2 <a href="#identifiers">Data Type Identifiers</a><br>&nbsp;&nbsp;&nbsp;&nbsp;3.3 <a href="#input-validations">Input Validations</a><br>&nbsp;&nbsp;&nbsp;&nbsp;3.4 <a href="#send-xml">Send XML to Server</a><br>&nbsp;&nbsp;&nbsp;&nbsp;3.5 <a href="#calculations">Calculations and Expressions</a><br>&nbsp;&nbsp;&nbsp;&nbsp;3.6 <a href="#dependencies">Data Value and Form Control Dependencies</a><br>&nbsp;&nbsp;&nbsp;&nbsp;3.7 <a href="#arrays">Expandable Form Control Groups (Arrays)</a><br>&nbsp;&nbsp;&nbsp;&nbsp;3.8 <a href="#security">Security Features</a><br>&nbsp;&nbsp;&nbsp;&nbsp;3.9 <a href="#confidence-instance">Confidence Scores</a><br>4 <a href="#ui-reqs">User Interface Requirements (Normative)</a><br>&nbsp;&nbsp;&nbsp;&nbsp;4.1 <a href="#backwards-features">Provide Functional Equivalents of HTML 4 Form Controls</a><br>&nbsp;&nbsp;&nbsp;&nbsp;4.2 <a href="#forwards-features">New Form Controls</a><br>&nbsp;&nbsp;&nbsp;&nbsp;4.3 <a href="#multi-page-form">Support Multiple Pages per Form, and Multiple Forms per
          Page</a><br>&nbsp;&nbsp;&nbsp;&nbsp;4.4 <a href="#input-devices">Support More Input Devices</a><br>&nbsp;&nbsp;&nbsp;&nbsp;4.5 <a href="#layout-alignment">Layout/Alignment</a><br>5 <a href="#future-req">Future Considerations (Non-Normative)</a><br>&nbsp;&nbsp;&nbsp;&nbsp;5.1 <a href="#custom-controls">Custom Defined Controls</a><br>&nbsp;&nbsp;&nbsp;&nbsp;5.2 <a href="#gui-enhancement">Further GUI Enhancements</a><br>&nbsp;&nbsp;&nbsp;&nbsp;5.3 <a href="#voice-enhancement">Voice Enhancements</a><br>&nbsp;&nbsp;&nbsp;&nbsp;5.4 <a href="#paper-enhancement">Paper Enhancements</a><br>&nbsp;&nbsp;&nbsp;&nbsp;5.5 <a href="#ambiguities">Representing Ambiguities</a><br>&nbsp;&nbsp;&nbsp;&nbsp;5.6 <a href="#dsig">Digital Signatures</a><br>&nbsp;&nbsp;&nbsp;&nbsp;5.7 <a href="#locale">Region Independence</a><br>&nbsp;&nbsp;&nbsp;&nbsp;5.8 <a href="#http-auth">HTTP Authentication Front-end</a><br>&nbsp;&nbsp;&nbsp;&nbsp;5.9 <a href="#save-resume">Saving and Resuming</a><br></p>
<h3>Appendices</h3><p class="toc">A <a href="#acknowledgments">Acknowledgements</a> (Non-Normative)<br>B <a href="#biblio">References</a> (Non-Normative)<br></p></div><hr><div class="body"> 
    <div class="div1">
<h2><a name="reqintro"></a>1 Introduction (Non-Normative)</h2> 
      <p> After careful consideration, the HTML Working Group decided that the
        goals for the next generation of forms are incompatible with preserving full
        backwards compatibility with browsers designed for earlier versions of HTML. A
        forms sub-group was formed within the HTML Working Group, later becoming the
        XForms Working Group. It is our objective to provide a clean new forms model
        ("XForms") based on a set of well-defined requirements. The requirements
        described in this document are based on experience with a broad spectrum of
        form applications.</p> 
      <p> This document provides a comprehensive set of requirements for the
        W3C's work on XForms. We envisage this work being conducted in several steps,
        starting with the development of a core forms module, followed by work on
        additional modules for specific features. The Modularization of XHTML provides
        a mechanism for defining modules which can be recombined as appropriate for the
        capabilities of different platforms.</p> 
      <div class="div2">
<h3><a name="reqintro-rationale"></a>1.1 Rationale</h3> 
        <p> Web forms are being used in various contexts as a standardized
          mechanism for bidirectional data exchange over the Web. In many occasions, it
          is desirable to enable an open data dialog between the recipient of a hypertext
          document and the sender. Forms need to provide effective support for various
          kinds of data exchange. The design of XForms focuses on the increasing demands
          for improved human-computer interaction as well as the interaction mechanisms
          between user agents (e.g. browsers) and servers.</p> 
        <p>The design of XForms focuses on the increasing demands for improved
          human-computer interaction as well as the interaction mechanisms between the
          browser (user agent) and the server.</p> 
        <p>To enable Web content developers to meet these challenges XForms
          will be designed to cleanly distinguish between form <em>instance
          data</em>, form description (called the <em>XForms Model</em>), and form
          presentation (called the <em>XForms User Interface</em>). The same form
          will be accessible on a full screen display, as a sheet of paper or using a
          handheld computer resting on your palm.</p> 
        <p>To meet the goals for richer presentation XForms will be designed
          for integration with other XML tag sets, such as XHTML, SVG for graphics and
          SMIL for multimedia forms. You will be able to use style sheet languages such
          as CSS and XSL to finely tune the presentation.</p> 
        <p>As the cost and size of Web servers continues to shrink, single chip
          implementations are now practical, and we can soon expect to see all kinds of
          devices with embedded servers. XHTML will be used for controlling such devices,
          reducing the need for custom device drivers. XForms will be designed to provide
          the richer user interface these applications will need.</p> 
        <p>It is generally best to catch input errors early. This can be
          achieved with form logic that works with the user to ensure that the form data
          values satisfy the appropriate consistency checks. For phone numbers and
          addresses, the checks will vary from one part of the world to another.</p> 
        <p>Complex forms are best presented as a sequence of sections, one
          section at a time. The ability to download the entire sequence in a single file
          makes it easy to fill out the form without a real-time connection to the Web
          server, and avoids the inevitable delays in reestablishing a connection to the
          server for each section.</p>
      </div>
      <div class="div2">
<h3><a name="reqintro-audience"></a>1.2 Target Audience</h3>
        <p>XForms provide considerable benefits compared with classic XHTML
          forms. In particular the separation of the purpose from the presentation of a
          form enables a separation of concerns such that differing skills can be applied
          to the design of a form. These skills may be embodied in a single person or
          many depending on both the sophistication of the Form being designed as well as
          the skills of individuals involved in the design process.</p> 
        <p>Individuals familiar with HTML 4 Forms will find XForms both more
          powerful as well as simpler. Specifically, XForms will make it simpler to build
          forms including the business logic, calculations, and form processing that in
          many cases prior to XForms has been done with scripting. The two primary roles
          associated with XForms authoring are the design of the purpose of the form as
          expressed in an XForms model as well as the design of the user interface and user
          interaction.</p> 
        <p>Server-side programmers are also part of the target audience. In the
          past, deploying forms on a Web site involved complex server-side scripting to
          accept, validate, and process incoming data. XForms will make this easier by
          providing a consistent, XML-based format for incoming data, as well as by
          providing a rich validation framework.</p> 
        <p>Finally, application vendors that produce products that interact
          with forms are part of the target audience. A vendor-neutral XForms model will
          provide an avenue for interoperability between various forms
          implementations.</p> 
      </div> 
    </div> 
    <div class="div1">
<h2><a name="charter-req"></a>2 Charter and Basic Requirements (Normative)</h2> 
      <div class="div2"> 
        
<h3><a name="in-xml"></a>2.1 Defined in XML, Usable in XML</h3> 
        <p>XForms will be an application of XML 1.0 plus Namespaces. It will be
          possible to define a rich form, including validations, dependencies, and basic
          calculations without the use of a scripting language. As an application of XML,
          it will be possible to combine XForms with other XML based languages such as
          XHTML.</p> 
      </div> 
      <div class="div2">
<h3><a name="w3c-integration"></a>2.2 W3C Integration</h3> 
        <p>The development of XForms will require interaction with many other
          W3C Working Groups. In particular, close coordination will be required with the
          following two Working Groups:</p> 
        <div class="div3">
<h4><a name="w3c-integration-p3p"></a>2.2.1 P3P</h4> 
          <p>The XForms Working Group will work with members of the P3P
            Specification Working Group to define functional requirements for integration
            of P3P and XForms. Close integration is important to assure that forms designed
            with XForms for the purpose of collection of personally-identifiable data allow
            the seamless association of privacy policies and preferences with the data
            being collected. The P3P specification Working Group will be asked to review
            the XForms Requirements and XForms Model specification.</p> 
        </div> 
        <div class="div3">
<h4><a name="w3c-integration-schema"></a>2.2.2 XML Schema</h4> 
          <p>To meet the needs for expressing the XForms Model, the XForms
            Working Group will utilize functionality from XML Schema in addition to
            developing additional form-specific properties. The XML Schema Working Group
            will be asked to review the XForms Requirements and XForms Model
            specification.</p> 
        </div> 
      </div> 
      <div class="div2">
<h3><a name="from-html4"></a>2.3 Migration from HTML 4</h3> 
        <p>XForms should be designed in such a way as to encourage users to
          make use of the new capabilities, rather than lingering on existing form
          technologies. Likewise, the design should encourage implementors to deploy user
          agents that implement XForms.</p> 
      </div> 
      <div class="div2">
<h3><a name="ease-of-authoring"></a>2.4 Ease of Authoring</h3> 
        <p>XForms should be straightforward to author by hand with a simple
          text editor, in order to encourage migration from existing HTML forms.</p> 
      </div> 
      <div class="div2">
<h3><a name="separate-p-from-p"></a>2.5 Separate Purpose from Presentation</h3> 
        <p>XForms data values should not be bound to a particular interface
          representation. Instead the XForms Model should represent the nature of the
          tasks the user is being asked to perform. The "purpose" of a form control may
          be the same on various devices, whereas the rendering may vary based on
          different capabilities.</p> 
      </div> 
      <div class="div2">
<h3><a name="device-independence"></a>2.6 Device Independence</h3> 
        <p>XForms should express the navigation paths within a form without
          implying specific user interface devices such as a mouse or keyboard. The
          navigation shouldn't rely on device-specific methods such as use of the
          "tab"-key.</p> 
        <p>It should be possible to express forms event handling for a broad
          range of devices. In previous versions of HTML some events were
          device-independent (e.g. onfocus, onblur, onchange), while others implied the
          availability of device-specific features (e.g. onmouseover, ondblclick). Within
          a single form, it should be possible to exploit events specific to different
          kinds of Web enabled devices, including conventional browsers, TV sets, set top
          boxes, palmtops and mobile phones.</p> 
      </div> 
      <div class="div2">
<h3><a name="scripting-interfaces"></a>2.7 Scripting Interfaces</h3> 
        <p>It should be possible to access and manipulate forms via a scripting
          interface. This is needed to allow the construction of specialized forms with
          behaviors going beyond the limits of the forms language itself. XForms should
          be accessible as part of an XML document, insensitive to changes in the
          enclosing document. Additional scripting interfaces specific to forms will be
          added.</p> 
      </div> 
      <div class="div2">
<h3><a name="unicode-i18n"></a>2.8 Unicode and Internationalization</h3> 
        <p>XForms should be fit for usage with non-western character sets,
          languages, and writing systems, including support for Unicode. It is required
          that nonwestern characters be preserved from their initial entry in a form
          control until their final destination and vice versa. It should be possible to
          provide for entry of data formats that do not force international users to
          adapt to western data formats if the corresponding data format is substantially
          different in other regions. </p> 
      </div> 
    </div> 
    <div class="div1">
<h2><a name="model-req"></a>3 XForms Model Requirements (Normative)</h2> 
      <p>XML Forms should be compatible with, build on, and extend (where
        necessary) the basic concepts, data structures, and data types defined by XML
        Schemas. XForms should address the needs of HTML authors as well as people who
        wish to use XForms with data schemas defined in XML Schema.</p> 
      <div class="div2">
<h3><a name="datatypes"></a>3.1 Data Types</h3> 
        <p>XForms will provide a set of common data types, and may facilitate
          the construction of custom data types.</p> 
      </div> 
      <div class="div2">
<h3><a name="identifiers"></a>3.2 Data Type Identifiers</h3> 
        <p>XForms should include the means to provide globally unique
          identifiers for types which can be used to establish that a given type is the
          same as used in other forms.</p> 
      </div> 
      <div class="div2">
<h3><a name="input-validations"></a>3.3 Input Validations</h3> 
        <p>XForms should be able to express restrictions on user-entered data,
          with enough sophistication to handle common cases, like "telephone number".
          XForms should define how the user agent should behave when the user-entered
          data conflicts with the restrictions defined by a data type.</p> 
      </div> 
      <div class="div2">
<h3><a name="send-xml"></a>3.4 Send XML to Server</h3> 
        <p>In addition to legacy formats, XForms will be able to send the
          submitted form instance data to the server as an XML document.</p> 
      </div> 
      <div class="div2">
<h3><a name="calculations"></a>3.5 Calculations and Expressions</h3> 
        <p>XForms should include simple calculations and expressions based on
          form data values. Common tasks like summing multiple data values and
          calculating sales tax should be possible. The expression syntax needs to be
          simple enough to be easily parsed and processed by a wide variety of user
          agents. It should be possible to escape out to a scripting language for
          advanced processing.</p> 
        <p>The XForms Working Group is aware of potential overlap with the XML
          Query Working Group in this area, and will review the documents produced by the
          XML Query Working Group. The XML Query Group will be asked to review the XForms
          Requirements and XForms Model specification.</p> 
      </div> 
      <div class="div2">
<h3><a name="dependencies"></a>3.6 Data Value and Form Control Dependencies</h3> 
        <p>XForms should be able to express dependencies between data values.
          It should be possible to constrain a form control so that it can only accept
          input if another specific data value has been filled. It should be possible to
          bind two or more form controls to the same data value, so that if the data
          value is updated, then the related form controls indicate that value.</p> 
      </div> 
      <div class="div2">
<h3><a name="arrays"></a>3.7 Expandable Form Control Groups (Arrays)</h3> 
        <p>For form control groups that support multiple entries, such as a
          line item on an order form, it should be possible for the form control to
          dynamically expand and contract to permit the addition or removal of further
          items. It should be possible to specify the initial, minimum, and maximum
          number of entries.</p> 
      </div> 
      <div class="div2">
<h3><a name="security"></a>3.8 Security Features</h3> 
        <p>It should be possible to perform secure, protocol-independent form
          transactions.</p> 
      </div> 
       
      <div class="div2">
<h3><a name="confidence-instance"></a>3.9 Confidence Scores</h3> 
        <p>Some input modalities (for example, speech recognition, handwriting
          recognition and optical character recognition) naturally result in
          uncertainties. Recognition engines may provide a measure of how confident the
          engine was that a given value was correctly recognized. It should be possible to  provide a
          means for such confidence scores to be included with form instance data. The representation of
          ambiguities is something that is potentially harder to deal with and falls
          under the section <a href="#future-req"><b>5 Future Considerations (Non-Normative)</b></a>.</p> 
      </div> 
    </div> 
    <div class="div1">
<h2><a name="ui-reqs"></a>4 User Interface Requirements (Normative)</h2> 
      <div class="div2"> 
        
<h3><a name="backwards-features"></a>4.1 Provide Functional Equivalents of HTML 4 Form Controls</h3> 
        <p>Every form of user interaction defined and commonly implemented in HTML 4 forms should be
          possible with XForms.</p> 
      </div> 
      <div class="div2">
<h3><a name="forwards-features"></a>4.2 New Form Controls</h3> 
        <p>Compared to current Web form technology, XForms should define richer
          form controls to match the expectations of designers, and to provide richer
          functionality for data acquisition. Designers should be given greater control
          over the visual appearance of form controls.</p> 
      </div> 
      <div class="div2">
<h3><a name="multi-page-form"></a>4.3 Support Multiple Pages per Form, and Multiple Forms per
          Page</h3> 
        <p>It should be possible for a form to be presented as two or more
          pages. This requirement permits the form to be treated as a single unit or as
          several parts. The form's logic should apply regardless of how it is split
          up.</p> 
        <p>Multiple independent forms should be able to exist within the same
          Web page.</p> 
      </div> 
      <div class="div2">
<h3><a name="input-devices"></a>4.4 Support More Input Devices</h3> 
        <p>Forms need to support a wide range of data acquisition techniques in
          addition to plain text. For instance, to enable the input of files, such as
          audio files, and the input of data streams from devices such as cameras,
          microphones and scanners. Also under consideration are pen-based inputs, which
          would allow signatures and other simple drawings to be entered directly into a
          form equipped with a suitable drawing canvas.</p> 
      </div> 
      <div class="div2">
<h3><a name="layout-alignment"></a>4.5 Layout/Alignment</h3> 
        <p>XForms should have no dependency on a particular presentation
          technology, for example XHTML tables.</p> 
        <p>We will investigate ways of achieving richer form layout and
          alignment on a wide variety of devices.</p> 
      </div> 
    </div> 
    <div class="div1">
<h2><a name="future-req"></a>5 Future Considerations (Non-Normative)</h2> 
      <p>XForms will be designed with the following features in mind, however
        these areas will not be addressed in the first release.</p>
         
      <div class="div2">
<h3><a name="custom-controls"></a>5.1 Custom Defined Controls</h3> 
        <p>There should be a way to define new form controls (perhaps using
          other markup languages such as SVG, perhaps with bitmap images) offering a
          custom look and feel but integrated into the forms model so that they
          internally behave and react like a standard form control.</p> 
      </div> 
      <div class="div2">
<h3><a name="gui-enhancement"></a>5.2 Further GUI Enhancements</h3> 
        <p>Further research into various additional graphical elements that
          will be useful as a part of XForms.</p> 
      </div> 
      <div class="div2">
<h3><a name="voice-enhancement"></a>5.3 Voice Enhancements</h3> 
        <p>Further research into ways to make XForms more useful to aural user
          agents.</p> 
      </div> 
      <div class="div2">
<h3><a name="paper-enhancement"></a>5.4 Paper Enhancements</h3> 
        <p>Further research into ways to make XForms more useful to paper
          processing and OCR user agents.</p> 
      </div> 
      <div class="div2">
<h3><a name="ambiguities"></a>5.5 Representing Ambiguities</h3> 
        <p>Some input modalities (for example, speech recognition, handwriting
          recognition and optical character recognition) naturally result in
          uncertainties and ambiguities. Did the user say "Boston" or "Austin" for the
          destination city? Study is needed into ways to represent such ambiguities in
          form instance data, and to make this available to servers when processing the
          form data.</p> 
      </div> 
      <div class="div2">
<h3><a name="dsig"></a>5.6 Digital Signatures</h3> 
        <p>Further research into what is needed to apply digital signatures to
          form presentation and data, possibly including the preservation of the form
          presentation exactly as the user experienced it.</p> 
      </div>
      <div class="div2">
<h3><a name="locale"></a>5.7 Region Independence</h3>
        <p>Forms designed for international access should to
          be able validate such data values taking the user's locale into account.
          Additionally, in forms designed for international access, labels, sizes and
          input constraints for data values should be able to adapt to the locale.</p>
        </div>
        <div class="div2">
<h3><a name="http-auth"></a>5.8 HTTP Authentication Front-end</h3>
        <p>Current user agents typically implement HTTP authentication with
          a pop-up window requesting name and password. It should be possible for XForms
          to be used as a front end for HTTP authentication.</p>
        </div> 
        <div class="div2">
<h3><a name="save-resume"></a>5.9 Saving and Resuming</h3> 
        <p>There needs to be a generalized way of preserving the changes the
          user has made to a form. This will make it possible for a user to save the
          form, and at a later time, to resume filling it out, perhaps from a different
          machine and perhaps with a different user interface. The ability to treat forms
          as persistent objects encapsulating state and behavior is needed for workflow
          applications where forms are passed from one user to another. It should be
          possible to merge independent updates to persistent forms in ways specific to
          individual applications.</p> 
      </div></div> 
  </div> 
  <div class="back"> 
    <div class="div1">
<h2><a name="acknowledgments"></a>A Acknowledgements (Non-Normative)</h2> 
      <p>This document was written with the participation of the XForms Working
        Group:</p> 
      <ul> 
        <li> 
          Steven Pemberton 
          , CWI 
           (<i>co-chair</i>)  
        </li><li> 
          Sebastian Schnitzenbaumer 
          , Mozquito Technologies 
           (<i>co-chair</i>)  
        </li><li> 
          Micah Dubinko 
          , Cardiff 
        </li> 
         
        <li>Driss Eddaifi
          , Ecole Mohammadia d'Ing&eacute;nieurs
        </li>
        <li>Najib Tounsi
          , Ecole Mohammadia d'Ing&eacute;nieurs
        </li>
        <li>Michalis Petropoulos
          , Enosys Markets, Inc.
        </li>
        <li> 
          Peter Stark 
          , Ericsson 
        </li> 
        <li> 
          Frank Boumphrey 
          , HTML Writer's Guild 
        </li> 
        <li> 
          Dave Raggett 
          , W3C 
        </li> 
        <li> 
          Roland Merrick 
          , IBM 
        </li><li> 
          T. V. Raman 
          , IBM 
        </li><li>Linda Bucksay Welsh
          , Intel</li> 
        <li>
          Gavin McKenzie 
          , JetForm Corporation 
        </li>
        <li>
          Rob McDougall 
          , JetForm Corporation 
        </li>
        <li>
          Ray Waldin 
          , Lexica, LLC 
        </li> 
        <li> 
          Tantek &Ccedil;elik 
          , Microsoft 
        </li> 
        <li> 
          Alex Hopmann 
          , Microsoft 
        </li> 
        <li>Dave Hyatt
          , Netscape/AOL
        </li>
        <li> 
          Eric Pollmann 
          , Netscape/AOL 
        </li><li>Tom Butcher
          , OpenDesign
        </li> 
        <li> 
          K. P. Lee 
          , Phillips 
        </li> 
        <li> 
          Roli Wendorf 
          , Phillips 
        </li> 
        <li> 
          Ted Wugofski 
          , Openwave 
        </li> 
        <li> 
          David Cleary 
          , Progress Software 
        </li> 
        <li> 
          Mike Mansell 
          , PureEdge 
        </li> 
        <li> 
          Dave Manning 
          , PureEdge 
        </li><li>Josef Dietl
          , Mozquito Technologies
        </li>
        <li>Michael Fergusson
          , Softquad
        </li> 
        <li> 
          Zoe Lacroix 
          , SurroMed, Inc. 
        </li> 
        <li> 
          Leigh Klotz 
          , Xerox 
        </li> 
      </ul> 
      <p>The XForms Working Group has benefited in its work from the
        participation and contributions of Invited Experts:</p> 
      <ul> 
        <li> 
          Tom Schnetlage 
          , University of Berkeley 
        </li> 
        <li> 
          Dan Gillman 
          , Federal Bureau of Labor Stastistics 
        </li> 
        <li> 
          Eliot Christian 
          , U.S. Geological Survey 
        </li> 
        <li> 
          Ashok Malhotra 
          , XML Schema and XML Query Working Groups (and
            IBM) 
        </li> 
      </ul> 
    </div>
    
    <div class="div1">
<h2><a name="biblio"></a>B References (Non-Normative)</h2>

      <dl> 
        <dt class="label"><a name="ref-authform"></a>AUTHFORM</dt><dd>
          <a href="http://standards.ieee.org/reading/ieee/std_public/description/busarch/754-1985_desc.html"><cite>User
          Agent Authentication Form Elements</cite></a>, Scott Lawrence, Jim Gettys, Paul
          Leach, 3 September 1998. Available at:
          http://www.w3.org/MarkUp/Group/Contrib/Lawrence/authform-980903.html</dd> 
        <dt class="label"><a name="ref-FML"></a>FML</dt><dd>
          <a href="http://www.mozquito.com/documentation/spec_xhtml-fml.html"><cite>Forms Markup
          Language (FML) 1.0</cite></a>, Sebastian Schnitzenbaumer, Malte Wedel, Muditha
          Gunatilake, Josef Dietl, 9 September 1999. Available at:
          http://www.mozquito.com/documentation/spec_xhtml-fml.html</dd> 
        <dt class="label"><a name="ref-FORMSHEET"></a>FORMSHEET</dt><dd>
          <a href="http://www.hpl.hp.co.uk/people/ak/doc/XForm.html"><cite>Formsheets
          and the XML Forms Language</cite></a>, Anders Kristensen, 11 May 1999.
          Available at: http://www.hpl.hp.co.uk/people/ak/doc/XForm.html</dd> 
        <dt class="label"><a name="ref-FUTUREFORMS"></a>FUTUREFORMS</dt><dd>
          <a href="http://www.w3.org/MarkUp/Group/WD-forms-ng.html"><cite>The Future of
          HTML Forms</cite></a>, Dave Raggett, 16 January 1999. Available at:
          http://www.w3.org/MarkUp/Group/WD-forms-ng.html</dd> 
        <dt class="label"><a name="ref-XFA"></a>XFA</dt><dd>
          <a href="http://www.w3.org/1999/05/XFA/xfa-formcalc.html"><cite>XFA-Template
          Version 1.0</cite></a>, Gavin McKenzie, 14 June 1999. Available at:
          http://www.w3.org/1999/05/XFA/xfa-formcalc.html</dd> 
        <dt class="label"><a name="ref-XFDL"></a>XFDL</dt><dd>
          <a href="http://www.w3.org/TR/NOTE-XFDL"><cite>Extensible Forms Description
          Language (XFDL) 4.0</cite></a>, John Boyer, Tim Bray, Maureen Gordon, 2
          September 1998. Available at: http://www.w3.org/TR/NOTE-XFDL</dd> 
      </dl>
    </div>
  </div>
</body></html>