index.html 27 KB

Raw Blame History Permalink

<!DOCTYPE html PUBLIC '-//W3C//DTD HTML 4.01 Transitional//EN' 'http://www.w3.org/TR/html4/loose.dtd'>
<html lang="en" dir="ltr">
<head>
    <title>The Network Information API</title>
    <meta http-equiv="Content-Type" content="text/html;charset=utf-8">


  <style type="text/css">
/*****************************************************************
 * ReSpec CSS
 * Robin Berjon (robin at berjon dot com)
 * v0.05 - 2009-07-31
 *****************************************************************/


/* --- INLINES --- */
em.rfc2119 {
    text-transform:     lowercase;
    font-variant:       small-caps;
    font-style:         normal;
    color:              #900;
}

h1 acronym, h2 acronym, h3 acronym, h4 acronym, h5 acronym, h6 acronym, a acronym,
h1 abbr, h2 abbr, h3 abbr, h4 abbr, h5 abbr, h6 abbr, a abbr {
    border: none;
}

dfn {
    font-weight:    bold;
}

a.internalDFN {
    color:  inherit;
    border-bottom:  1px solid #99c;
    text-decoration:    none;
}

a.externalDFN {
    color:  inherit;
    border-bottom:  medium dotted #ccc;
    text-decoration:    none;
}

a.bibref {
    text-decoration:    none;
}

code {
    color:  #ff4500;
}


/* --- WEB IDL --- */
pre.idl {
    border-top: 1px solid #90b8de;
    border-bottom: 1px solid #90b8de;
    padding:    1em;
    line-height:    120%;
}

pre.idl::before {
    content:    "WebIDL";
    display:    block;
    width:      150px;
    background: #90b8de;
    color:  #fff;
    font-family:    initial;
    padding:    3px;
    font-weight:    bold;
    margin: -1em 0 1em -1em;
}

.idlType {
    color:  #ff4500;
    font-weight:    bold;
    text-decoration:    none;
}

/*.idlModule*/
/*.idlModuleID*/
/*.idlInterface*/
.idlInterfaceID {
    font-weight:    bold;
    color:  #005a9c;
}

.idlSuperclass {
    font-style: italic;
    color:  #005a9c;
}

/*.idlAttribute*/
.idlAttrType, .idlFieldType {
    color:  #005a9c;
}
.idlAttrName, .idlFieldName {
    color:  #ff4500;
}
.idlAttrName a, .idlFieldName a {
    color:  #ff4500;
    border-bottom:  1px dotted #ff4500;
    text-decoration: none;
}

/*.idlMethod*/
.idlMethType {
    color:  #005a9c;
}
.idlMethName {
    color:  #ff4500;
}
.idlMethName a {
    color:  #ff4500;
    border-bottom:  1px dotted #ff4500;
    text-decoration: none;
}

/*.idlParam*/
.idlParamType {
    color:  #005a9c;
}
.idlParamName {
    font-style: italic;
}

.extAttr {
    color:  #666;
}

/*.idlConst*/
.idlConstType {
    color:  #005a9c;
}
.idlConstName {
    color:  #ff4500;
}
.idlConstName a {
    color:  #ff4500;
    border-bottom:  1px dotted #ff4500;
    text-decoration: none;
}

/*.idlException*/
.idlExceptionID {
    font-weight:    bold;
    color:  #c00;
}

.idlTypedefID, .idlTypedefType {
    color:  #005a9c;
}

.idlRaises, .idlRaises a.idlType, .idlRaises a.idlType code, .excName a, .excName a code {
    color:  #c00;
    font-weight:    normal;
}

.excName a {
    font-family:    monospace;
}

.idlRaises a.idlType, .excName a.idlType {
    border-bottom:  1px dotted #c00;
}

.excGetSetTrue, .excGetSetFalse, .prmNullTrue, .prmNullFalse, .prmOptTrue, .prmOptFalse {
    width:  45px;
    text-align: center;
}
.excGetSetTrue, .prmNullTrue, .prmOptTrue { color:  #0c0; }
.excGetSetFalse, .prmNullFalse, .prmOptFalse { color:  #c00; }

.idlImplements a {
    font-weight:    bold;
}

dl.attributes, dl.methods, dl.constants, dl.fields {
    margin-left:    2em;
}

.attributes dt, .methods dt, .constants dt, .fields dt {
    font-weight:    normal;
}

.attributes dt code, .methods dt code, .constants dt code, .fields dt code {
    font-weight:    bold;
    color:  #000;
    font-family:    monospace;
}

.attributes dt code, .fields dt code {
    background:  #ffffd2;
}

.attributes dt .idlAttrType code, .fields dt .idlFieldType code {
    color:  #005a9c;
    background:  transparent;
    font-family:    inherit;
    font-weight:    normal;
    font-style: italic;
}

.methods dt code {
    background:  #d9e6f8;
}

.constants dt code {
    background:  #ddffd2;
}

.attributes dd, .methods dd, .constants dd, .fields dd {
    margin-bottom:  1em;
}

table.parameters, table.exceptions {
    border-spacing: 0;
    border-collapse:    collapse;
    margin: 0.5em 0;
    width:  100%;
}
table.parameters { border-bottom:  1px solid #90b8de; }
table.exceptions { border-bottom:  1px solid #deb890; }

.parameters th, .exceptions th {
    color:  #fff;
    padding:    3px 5px;
    text-align: left;
    font-family:    initial;
    font-weight:    normal;
    text-shadow:    #666 1px 1px 0;
}
.parameters th { background: #90b8de; }
.exceptions th { background: #deb890; }

.parameters td, .exceptions td {
    padding:    3px 10px;
    border-top: 1px solid #ddd;
    vertical-align: top;
}

.parameters tr:first-child td, .exceptions tr:first-child td {
    border-top: none;
}

.parameters td.prmName, .exceptions td.excName, .exceptions td.excCodeName {
    width:  100px;
}

.parameters td.prmType {
    width:  120px;
}

table.exceptions table {
    border-spacing: 0;
    border-collapse:    collapse;
    width:  100%;
}

/* --- TOC --- */
.toc a {
    text-decoration:    none;
}

a .secno {
    color:  #000;
}

/* --- TABLE --- */
table.simple {
    border-spacing: 0;
    border-collapse:    collapse;
    border-bottom:  3px solid #005a9c;
}

.simple th {
    background: #005a9c;
    color:  #fff;
    padding:    3px 5px;
    text-align: left;
}

.simple th[scope="row"] {
    background: inherit;
    color:  inherit;
    border-top: 1px solid #ddd;
}

.simple td {
    padding:    3px 10px;
    border-top: 1px solid #ddd;
}

.simple tr:nth-child(even) {
    background: #f0f6ff;
}

/* --- DL --- */
.section dd > p:first-child {
    margin-top: 0;
}

.section dd > p:last-child {
    margin-bottom: 0;
}

.section dd {
    margin-bottom:  1em;
}

.section dl.attrs dd, .section dl.eldef dd {
    margin-bottom:  0;
}

/* --- EXAMPLES --- */
pre.example {
    border-top: 1px solid #ff4500;
    border-bottom: 1px solid #ff4500;
    padding:    1em;
    margin-top: 1em;
}

pre.example::before {
    content:    "Example";
    display:    block;
    width:      150px;
    background: #ff4500;
    color:  #fff;
    font-family:    initial;
    padding:    3px;
    font-weight:    bold;
    margin: -1em 0 1em -1em;
}

/* --- EDITORIAL NOTES --- */
.issue {
    padding:    1em;
    margin: 1em 0em 0em;
    border: 1px solid #f00;
    background: #ffc;
}

.issue::before {
    content:    "Issue";
    display:    block;
    width:  150px;
    margin: -1.5em 0 0.5em 0;
    font-weight:    bold;
    border: 1px solid #f00;
    background: #fff;
    padding:    3px 1em;
}

.note {
    margin: 1em 0em 0em;
    padding:    1em;
    border: 2px solid #cff6d9;
    background: #e2fff0;
}

.note::before {
    content:    "Note";
    display:    block;
    width:  150px;
    margin: -1.5em 0 0.5em 0;
    font-weight:    bold;
    border: 1px solid #cff6d9;
    background: #fff;
    padding:    3px 1em;
}

/* --- Best Practices --- */
div.practice {
    border: solid #bebebe 1px;
    margin: 2em 1em 1em 2em;
}

span.practicelab {
    margin: 1.5em 0.5em 1em 1em;
    font-weight: bold;
    font-style: italic;
}

span.practicelab   { background: #dfffff; }

span.practicelab {
    position: relative;
    padding: 0 0.5em;
    top: -1.5em;
}

p.practicedesc {
    margin: 1.5em 0.5em 1em 1em;
}

@media screen {
    p.practicedesc {
        position: relative;
        top: -2em;
        padding: 0;
        margin: 1.5em 0.5em -1em 1em;
}

/* --- SYNTAX HIGHLIGHTING --- */
pre.sh_sourceCode {
  background-color: white;
  color: black;
  font-style: normal;
  font-weight: normal;
}

pre.sh_sourceCode .sh_keyword { color: #005a9c; font-weight: bold; }           /* language keywords */
pre.sh_sourceCode .sh_type { color: #666; }                            /* basic types */
pre.sh_sourceCode .sh_usertype { color: teal; }                             /* user defined types */
pre.sh_sourceCode .sh_string { color: red; font-family: monospace; }        /* strings and chars */
pre.sh_sourceCode .sh_regexp { color: orange; font-family: monospace; }     /* regular expressions */
pre.sh_sourceCode .sh_specialchar { color: 	#ffc0cb; font-family: monospace; }  /* e.g., \n, \t, \\ */
pre.sh_sourceCode .sh_comment { color: #A52A2A; font-style: italic; }         /* comments */
pre.sh_sourceCode .sh_number { color: purple; }                             /* literal numbers */
pre.sh_sourceCode .sh_preproc { color: #00008B; font-weight: bold; }       /* e.g., #include, import */
pre.sh_sourceCode .sh_symbol { color: blue; }                            /* e.g., *, + */
pre.sh_sourceCode .sh_function { color: black; font-weight: bold; }         /* function calls and declarations */
pre.sh_sourceCode .sh_cbracket { color: red; }                              /* block brackets (e.g., {, }) */
pre.sh_sourceCode .sh_todo { font-weight: bold; background-color: #00FFFF; }   /* TODO and FIXME */

/* Predefined variables and functions (for instance glsl) */
pre.sh_sourceCode .sh_predef_var { color: #00008B; }
pre.sh_sourceCode .sh_predef_func { color: #00008B; font-weight: bold; }

/* for OOP */
pre.sh_sourceCode .sh_classname { color: teal; }

/* line numbers (not yet implemented) */
pre.sh_sourceCode .sh_linenum { display: none; }

/* Internet related */
pre.sh_sourceCode .sh_url { color: blue; text-decoration: underline; font-family: monospace; }

/* for ChangeLog and Log files */
pre.sh_sourceCode .sh_date { color: blue; font-weight: bold; }
pre.sh_sourceCode .sh_time, pre.sh_sourceCode .sh_file { color: #00008B; font-weight: bold; }
pre.sh_sourceCode .sh_ip, pre.sh_sourceCode .sh_name { color: #006400; }

/* for Prolog, Perl... */
pre.sh_sourceCode .sh_variable { color: #006400; }

/* for LaTeX */
pre.sh_sourceCode .sh_italics { color: #006400; font-style: italic; }
pre.sh_sourceCode .sh_bold { color: #006400; font-weight: bold; }
pre.sh_sourceCode .sh_underline { color: #006400; text-decoration: underline; }
pre.sh_sourceCode .sh_fixed { color: green; font-family: monospace; }
pre.sh_sourceCode .sh_argument { color: #006400; }
pre.sh_sourceCode .sh_optionalargument { color: purple; }
pre.sh_sourceCode .sh_math { color: orange; }
pre.sh_sourceCode .sh_bibtex { color: blue; }

/* for diffs */
pre.sh_sourceCode .sh_oldfile { color: orange; }
pre.sh_sourceCode .sh_newfile { color: #006400; }
pre.sh_sourceCode .sh_difflines { color: blue; }

/* for css */
pre.sh_sourceCode .sh_selector { color: purple; }
pre.sh_sourceCode .sh_property { color: blue; }
pre.sh_sourceCode .sh_value { color: #006400; font-style: italic; }

/* other */
pre.sh_sourceCode .sh_section { color: black; font-weight: bold; }
pre.sh_sourceCode .sh_paren { color: red; }
pre.sh_sourceCode .sh_attribute { color: #006400; }

</style><link charset="utf-8" type="text/css" rel="stylesheet" href="http://www.w3.org/StyleSheets/TR/W3C-WD"></head>

  <body style="display: inherit;"><div class="head"><p><a href="http://www.w3.org/"><img src="http://www.w3.org/Icons/w3c_home" alt="W3C" height="48" width="72"></a></p><h1 class="title" id="title">The Network Information API</h1><h2 id="w3c-working-draft-07-june-2011">W3C Working Draft 07 June 2011</h2><dl><dt>This version:</dt><dd><a href="http://www.w3.org/TR/2011/WD-netinfo-api-20110607/">http://www.w3.org/TR/2011/WD-netinfo-api-20110607/</a></dd><dt>Latest published version:</dt><dd><a href="http://www.w3.org/TR/netinfo-api/">http://www.w3.org/TR/netinfo-api/</a></dd><dt>Latest editor's draft:</dt><dd><a href="http://dev.w3.org/2009/dap/netinfo/">http://dev.w3.org/2009/dap/netinfo/</a></dd><dt>Editors:</dt><dd><span>Suresh Chitturi</span>, <a href="http://rim.com/">Research In Motion (RIM)</a></dd>
<dd><a href="http://berjon.com/">Robin Berjon</a>, <a href="http://robineko.com/">Robineko</a></dd>
</dl><p class="copyright"><a href="http://www.w3.org/Consortium/Legal/ipr-notice#Copyright">Copyright</a> © 2011 <a href="http://www.w3.org/"><acronym title="World Wide Web Consortium">W3C</acronym></a><sup>®</sup> (<a href="http://www.csail.mit.edu/"><acronym title="Massachusetts Institute of Technology">MIT</acronym></a>, <a href="http://www.ercim.eu/"><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><hr></div>
    <div class="introductory section" id="abstract"><h2>Abstract</h2>
      The Network Information API provides an interface for Web Applications to access the underlying
      network information (connection info) of the device.
    </div><div id="sotd" class="introductory section"><h2>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>
        The functionality described in this specification was initially specified as part of the
        <a href="http://www.w3.org/TR/system-info-api/">System Information API</a> but has been
        extracted in order to be more readily available, more straightforward to implement, and
        in order to produce a specification that could be implemented on its own merits without
        interference with other, often unrelated, features.
      </p>
    <p>This document was published by the <a href="http://www.w3.org/2009/dap/">Device APIs and Policy Working Group</a> as a First Public Working Draft. This document is intended to become a W3C Recommendation. If you wish to make comments regarding this document, please send them to <a href="mailto:public-device-apis@w3.org">public-device-apis@w3.org</a> (<a href="mailto:public-device-apis-request@w3.org?subject=subscribe">subscribe</a>, <a href="http://lists.w3.org/Archives/Public/public-device-apis/">archives</a>). All feedback is welcome.</p><p>Publication as a Working Draft does not imply endorsement by the W3C Membership. This is a draft document and may be updated, replaced or obsoleted by other documents at any time. It is inappropriate to cite this document as other than work in progress.</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 href="http://www.w3.org/2004/01/pp-impl/43696/status" rel="disclosure">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="section" id="toc"><h2 class="introductory">Table of Contents</h2><ul class="toc"><li class="tocline"><a class="tocxref" href="#conformance"><span class="secno">1. </span>Conformance</a></li><li class="tocline"><a class="tocxref" href="#introduction"><span class="secno">2. </span>Introduction</a></li><li class="tocline"><a class="tocxref" href="#api-description"><span class="secno">3. </span>API Description</a><ul class="toc"><li class="tocline"><a class="tocxref" href="#the-networkinfo-interface"><span class="secno">3.1 </span>The <span class="idlType formerLink idlType"><code>NetworkInfo</code></span> interface</a><ul class="toc"><li class="tocline"><a class="tocxref" href="#attributes"><span class="secno">3.1.1 </span>Attributes</a></li></ul></li><li class="tocline"><a class="tocxref" href="#the-connection-interface"><span class="secno">3.2 </span>The <span class="idlType formerLink idlType"><code>Connection</code></span> interface</a><ul class="toc"><li class="tocline"><a class="tocxref" href="#attributes-1"><span class="secno">3.2.1 </span>Attributes</a></li></ul></li></ul></li><li class="tocline"><a class="tocxref" href="#changes-in-connection-information"><span class="secno">4. </span>Changes in connection information</a></li><li class="tocline"><a class="tocxref" href="#acknowledgements"><span class="secno">A. </span>Acknowledgements</a></li><li class="tocline"><a class="tocxref" href="#references"><span class="secno">B. </span>References</a><ul class="toc"><li class="tocline"><a class="tocxref" href="#normative-references"><span class="secno">B.1 </span>Normative references</a></li><li class="tocline"><a class="tocxref" href="#informative-references"><span class="secno">B.2 </span>Informative references</a></li></ul></li></ul></div>


    <div class="section" id="conformance"><!--OddPage--><h2><span class="secno">1. </span>Conformance</h2><p>As well as sections marked as non-normative, all authoring guidelines, diagrams, examples, and notes in this specification are non-normative. Everything else in this specification is normative.</p>
<p>The key words <em title="must" class="rfc2119">must</em>, <em title="must not" class="rfc2119">must not</em>, <em title="required" class="rfc2119">required</em>, <em title="should" class="rfc2119">should</em>, <em title="should not" class="rfc2119">should not</em>, <em title="recommended" class="rfc2119">recommended</em>, <em title="may" class="rfc2119">may</em>, and <em title="optional" class="rfc2119">optional</em> in this specification are to be interpreted as described in [<cite><a href="#bib-RFC2119" rel="biblioentry" class="bibref">RFC2119</a></cite>].</p>

      <p>
        This specification defines conformance criteria that apply to a single product: the <dfn id="dfn-user-agent">user agent</dfn> that
        implements the interfaces that it contains.
      </p>
      <p>
        Implementations that use ECMAScript to expose the APIs defined in this specification must implement them in a manner
        consistent with the ECMAScript Bindings defined in the Web IDL specification [<cite><a href="#bib-WEBIDL" rel="biblioentry" class="bibref">WEBIDL</a></cite>].
      </p>
    </div>

    <div id="introduction" class="informative section">
      <!--OddPage--><h2><span class="secno">2. </span>Introduction</h2><p><em>This section is non-normative.</em></p>
      <p>
        The Network Information API provides an interface enabling Web applications to access the underlying network
        information (connection type) of the device.
	    </p>
    	<pre class="example sh_javascript sh_sourceCode"><span class="sh_comment">// add a class on the root list that matches a specific connection type</span>
<span class="sh_keyword">function</span> <span class="sh_function">updateConnectionClass</span> <span class="sh_symbol">()</span> <span class="sh_cbracket">{</span>
    <span class="sh_keyword">var</span> root <span class="sh_symbol">=</span> document<span class="sh_symbol">.</span>documentElement<span class="sh_symbol">,</span>
        types <span class="sh_symbol">=</span> <span class="sh_string">"unknown ethernet wifi 2g 3g 4g none"</span><span class="sh_symbol">.</span><span class="sh_function">split</span><span class="sh_symbol">(</span><span class="sh_string">" "</span><span class="sh_symbol">);</span>
    <span class="sh_keyword">for</span> <span class="sh_symbol">(</span><span class="sh_keyword">var</span> i <span class="sh_symbol">=</span> <span class="sh_number">0</span><span class="sh_symbol">,</span> n <span class="sh_symbol">=</span> types<span class="sh_symbol">.</span>length<span class="sh_symbol">;</span> i <span class="sh_symbol">&lt;</span> n<span class="sh_symbol">;</span> i<span class="sh_symbol">++)</span> root<span class="sh_symbol">.</span>classList<span class="sh_symbol">.</span><span class="sh_function">remove</span><span class="sh_symbol">(</span><span class="sh_string">"network-"</span> <span class="sh_symbol">+</span> types<span class="sh_symbol">[</span>i<span class="sh_symbol">])</span>
    root<span class="sh_symbol">.</span>classList<span class="sh_symbol">.</span><span class="sh_function">add</span><span class="sh_symbol">(</span><span class="sh_string">"network-"</span> <span class="sh_symbol">+</span> navigator<span class="sh_symbol">.</span>connection<span class="sh_symbol">.</span>type<span class="sh_symbol">);</span>
<span class="sh_cbracket">}</span>
window<span class="sh_symbol">.</span>onload <span class="sh_symbol">=</span> window<span class="sh_symbol">.</span>ononline <span class="sh_symbol">=</span> window<span class="sh_symbol">.</span>onoffline <span class="sh_symbol">=</span> updateConnectionClass<span class="sh_symbol">;</span></pre>
    </div>

	  <div class="section" id="api-description">
      <!--OddPage--><h2><span class="secno">3. </span>API Description</h2>
      <div class="section" id="the-networkinfo-interface">
        <h3><span class="secno">3.1 </span>The <a class="idlType" href="#idl-def-NetworkInfo"><code>NetworkInfo</code></a> interface</h3>
        <p>
          The <a class="idlType" href="#idl-def-NetworkInfo"><code>NetworkInfo</code></a> interface is exposed on the
          <code>Navigator</code> object.
        </p>
        <pre class="idl"><span class="idlImplements"><a>Navigator</a> implements <a class="idlType" href="#idl-def-NetworkInfo"><code>NetworkInfo</code></a>;</span></pre><div class="idlImplementsDesc"><p>All instances of the <code><a>Navigator</a></code> type are defined to also implement the <a class="idlType" href="#idl-def-NetworkInfo"><code>NetworkInfo</code></a> interface.</p></div>
        <pre class="idl"><span class="idlInterface" id="idl-def-NetworkInfo">[<span class="extAttr">NoInterfaceObject</span>]
interface <span class="idlInterfaceID">NetworkInfo</span> {
<span class="idlAttribute">    readonly attribute <span class="idlAttrType"><a class="idlType" href="#idl-def-Connection"><code>Connection</code></a></span> <span class="idlAttrName"><a href="#widl-NetworkInfo-connection">connection</a></span>;</span>
};</span>
</pre><div class="section" id="attributes"><h4><span class="secno">3.1.1 </span>Attributes</h4><dl class="attributes"><dt id="widl-NetworkInfo-connection"><code>connection</code> of type <span class="idlAttrType"><a class="idlType" href="#idl-def-Connection"><code>Connection</code></a></span>, readonly</dt><dd>
            The object from which connection information is accessed.
          <div><em>No exceptions.</em></div></dd></dl></div>
      </div>

      <div class="section" id="the-connection-interface">
		    <h3><span class="secno">3.2 </span>The <a class="idlType" href="#idl-def-Connection"><code>Connection</code></a> interface</h3>
		    <p>
			    The <a class="idlType" href="#idl-def-Connection"><code>Connection</code></a> interface provides a handle to the device's connection information.
		    </p>
        <pre class="idl"><span class="idlInterface" id="idl-def-Connection">[<span class="extAttr">NoInterfaceObject</span>]
interface <span class="idlInterfaceID">Connection</span> {
<span class="idlAttribute">    readonly attribute <span class="idlAttrType"><a>DOMString</a></span> <span class="idlAttrName"><a href="#widl-Connection-type">type</a></span>;</span>
};</span>
</pre><div class="section" id="attributes-1"><h4><span class="secno">3.2.1 </span>Attributes</h4><dl class="attributes"><dt id="widl-Connection-type"><code>type</code> of type <span class="idlAttrType"><a>DOMString</a></span>, readonly</dt><dd>
            <p>
          		Exposes the current connection type. The value returned is one of the following strings,
          		case-sensitively: <code>unknown</code>, <code>ethernet</code>, <code>wifi</code>, <code>2g</code>,
          		<code>3g</code>, <code>4g</code>, <code>none</code>. Implementers may expose other values,
          		in which case it is <em title="recommended" class="rfc2119">recommended</em> that they are prefixed with a vendor-specific identifier, e.g.
          		<code>acme-superluminal</code>. Other identifiers may be added in the future.
            </p>
            <p class="issue">
              The existing implementation, Android, uses integer constants for this (which is a shame since
              other parts of the Android platform use the more reasonable strings instead). Should we just go with
              it?
            </p>
          <div><em>No exceptions.</em></div></dd></dl></div>
	    </div>
	  </div>

	  <div class="section" id="changes-in-connection-information">
	   <!--OddPage--><h2><span class="secno">4. </span>Changes in connection information</h2>
	   <p>
	     When changes in the underlying device's connection information occur, the <a class="internalDFN" href="#dfn-user-agent">user agent</a> <em title="must" class="rfc2119">must</em>
	     <a class="externalDFN">queue a task</a> to <a class="externalDFN">fire a simple event</a> named
	     either <code>online</code> or <code>offline</code> depending on the applicable value, as defined
	     in [<cite><a href="#bib-HTML5" rel="biblioentry" class="bibref">HTML5</a></cite>].
	   </p>
	   <p>
	     Note that this may cause the same event (<code>online</code> or <code>offline</code>) to be triggered
	     multiple times in succession rather than toggling between either value.
	   </p>
	   <p class="issue">
	     There is discussion about whether this justifies a new event or not. People may have some initialisation
	     code that runs on <code>online</code> which they don't expect to have to run when one switches from
	     Wi-Fi to ethernet. By its very nature, such code should be able to run multiple times with no harm, but
	     it may still be wasteful to do so.
	   </p>
	  </div>

    <div id="acknowledgements" class="appendix section">
      <!--OddPage--><h2><span class="secno">A. </span>Acknowledgements</h2>
      <p>
        TBD
      </p>
    </div>


<div class="appendix section" id="references"><!--OddPage--><h2><span class="secno">B. </span>References</h2><div class="section" id="normative-references"><h3><span class="secno">B.1 </span>Normative references</h3><dl class="bibliography"><dt id="bib-HTML5">[HTML5]</dt><dd>Ian Hickson; David Hyatt. <a href="http://www.w3.org/TR/2010/WD-html5-20100304/"><cite>HTML 5.</cite></a> 4 March 2010. W3C Working Draft. (Work in progress.) URL: <a href="http://www.w3.org/TR/2010/WD-html5-20100304/">http://www.w3.org/TR/2010/WD-html5-20100304/</a>
</dd><dt id="bib-RFC2119">[RFC2119]</dt><dd>S. Bradner. <a href="http://www.ietf.org/rfc/rfc2119.txt"><cite>Key words for use in RFCs to Indicate Requirement Levels.</cite></a> March 1997. Internet RFC 2119.  URL: <a href="http://www.ietf.org/rfc/rfc2119.txt">http://www.ietf.org/rfc/rfc2119.txt</a>
</dd><dt id="bib-WEBIDL">[WEBIDL]</dt><dd>Cameron McCormack. <a href="http://www.w3.org/TR/2008/WD-WebIDL-20081219"><cite>Web IDL.</cite></a> 19 December 2008. W3C Working Draft. (Work in progress.) URL: <a href="http://www.w3.org/TR/2008/WD-WebIDL-20081219">http://www.w3.org/TR/2008/WD-WebIDL-20081219</a>
</dd></dl></div><div class="section" id="informative-references"><h3><span class="secno">B.2 </span>Informative references</h3><p>No informative references.</p></div></div></body></html>