This document defines an XMPP protocol extension for communicating information about the web pages a user visits.
WARNING: This Standards-Track document is Experimental. Publication as an XMPP Extension Protocol does not imply approval of this proposal by the XMPP Standards Foundation. Implementation of the protocol described herein is encouraged in exploratory implementations, but production systems should not deploy implementations of this protocol until it advances to a status of Draft.
            Series: XEP
            Number: 0195
            Publisher: XMPP Standards Foundation
            Status: 
            Experimental
            Type:
            Standards Track
            Version: 0.2
            Last Updated: 2007-10-03
                Approving Body: XMPP Council
Dependencies: XMPP Core, XMPP IM, XEP-0060, XEP-0163
                Supersedes: None
                Superseded By: None
            Short Name: TO BE ASSIGNED
              Wiki Page: <http://wiki.jabber.org/index.php/User Browsing (XEP-0195)>
            
        JabberID: 
        stpeter@jabber.org
        URI: 
        https://stpeter.im/
The preferred venue for discussion of this document is the Standards discussion list: <http://mail.jabber.org/mailman/listinfo/standards>.
Errata may be sent to <editor@xmpp.org>.
The Extensible Messaging and Presence Protocol (XMPP) is defined in the XMPP Core (RFC 3920) and XMPP IM (RFC 3921) specifications contributed by the XMPP Standards Foundation to the Internet Standards Process, which is managed by the Internet Engineering Task Force in accordance with RFC 2026. Any protocol defined in this document has been developed outside the Internet Standards Process and is to be understood as an extension to XMPP rather than as an evolution, development, or modification of XMPP itself.
The following keywords as used in this document are to be interpreted as described in RFC 2119: "MUST", "SHALL", "REQUIRED"; "MUST NOT", "SHALL NOT"; "SHOULD", "RECOMMENDED"; "SHOULD NOT", "NOT RECOMMENDED"; "MAY", "OPTIONAL".
1.  Introduction
2.  Protocol
   
      2.1.  Container Element and Child Elements
   
      2.2.  Transport Mechanism
3.  Security Considerations
4.  IANA Considerations
5.  XMPP Registrar Considerations
   
      5.1.  Protocol Namespaces
6.  XML Schema
Notes
Revision History
Publish-Subscribe [1] and Personal Eventing via Pubsub [2] can be used to publish a wide variety of "extended presence" information about users. This document specifies an extended presence payload format that communicates information about the web pages a user visits. This information may be of interest to a user's contacts and can also be used in social networking applications (e.g., co-browsing and web swarms).
Information about web pages is provided by the user (or automated integration with browsers or other systems) and is propagated on the network by the user's client. The information container for web page data is a <page/> element that is qualified by the 'http://www.xmpp.org/extensions/xep-0195.html#ns' namespace (see Protocol Namespaces regarding issuance of one or more permanent namespaces). The web page information itself is provided as the XML character data of the following children of the <page/> element:
| Element | Description | Example | Datatype | Inclusion | 
|---|---|---|---|---|
| description | The value of the "description" META tag | The weblog of Peter Saint-Andre | xs:string | OPTIONAL | 
| keywords | The value of the "keywords" META tag | stpeter, Peter Saint-Andre, weblog, jabber, xmpp | xs:string | OPTIONAL | 
| title | The value of the <title/> element | one small voice | xs:string | OPTIONAL | 
| uri | The URI of the page (usually but not necessarily an HTTP URL) | https://stpeter.im/ | xs:anyURI | REQUIRED | 
NOTE: The datatypes specified above are defined in XML Schema Part 2 [3].
When a user visits a web page, its client may publish that fact to a PEP node whose NodeID is "http://www.xmpp.org/extensions/xep-0195.html#ns" (see Protocol Namespaces regarding issuance of one or more permanent namespaces) or to a generic pubsub node. Because browsing information is not pure presence information and can change independently of the user's availability, it SHOULD NOT be provided as an extension to the <presence/> stanza type.
Example 1. User Publishes Browsing Information
<iq type='set' from='stpeter@jabber.org/work' id='browsing1'>
  <pubsub xmlns='http://jabber.org/protocol/pubsub'>
    <publish node='http://www.xmpp.org/extensions/xep-0195.html#ns'>
      <item id='da6abe63d1e5ed45a6de466732abff72e6fccb93'>
        <page xmlns='http://www.xmpp.org/extensions/xep-0195.html#ns'>
          <uri>https://stpeter.im/</uri>
        </page>
      </item>
    </publish>
  </pubsub>
</iq>
    The browsing information is then delivered to all subscribers:
Example 2. Browsing Information is Delivered to All Subscribers
<message from='stpeter@jabber.org' to='maineboy@jabber.org'>
  <event xmlns='http://jabber.org/protocol/pubsub#event'>
    <items node='http://www.xmpp.org/extensions/xep-0195.html#ns'>
      <item id='da6abe63d1e5ed45a6de466732abff72e6fccb93'>
        <page xmlns='http://www.xmpp.org/extensions/xep-0195.html#ns'>
          <uri>https://stpeter.im/</uri>
        </page>
      </item>
    </items>
  </event>
</message>
[ ... ]
    When the user stops browsing the page (e.g., by closing the browser window or tab), the user's client SHOULD send an empty <page/> element with the same ItemID:
Example 3. User Publishes Stop Information
<iq type='set' from='stpeter@jabber.org/work' id='browsing2'>
  <pubsub xmlns='http://jabber.org/protocol/pubsub'>
    <publish node='http://www.xmpp.org/extensions/xep-0195.html#ns'>
      <item id='da6abe63d1e5ed45a6de466732abff72e6fccb93'>
        <page xmlns='http://www.xmpp.org/extensions/xep-0195.html#ns'/>
      </item>
    </publish>
  </pubsub>
</iq>
    Example 4. Stop Information is Delivered to All Subscribers
<message from='stpeter@jabber.org' to='maineboy@jabber.org'>
  <event xmlns='http://jabber.org/protocol/pubsub#event'>
    <items node='http://www.xmpp.org/extensions/xep-0195.html#ns'>
      <item id='da6abe63d1e5ed45a6de466732abff72e6fccb93'>
        <page xmlns='http://www.xmpp.org/extensions/xep-0195.html#ns'/>
      </item>
    </items>
  </event>
</message>
[ ... ]
    The web pages that a user visits may be sensitive. A client MUST provide a way for a user to configure which pages or types of pages will not be published (e.g., via user preferences).
This document requires no interaction with the Internet Assigned Numbers Authority (IANA) [4].
Until this specification advances to a status of Draft, its associated namespace shall be "http://www.xmpp.org/extensions/xep-0195.html#ns"; upon advancement of this specification, the XMPP Registrar [5] shall issue a permanent namespace in accordance with the process defined in Section 4 of XMPP Registrar Function [6].
<?xml version='1.0' encoding='UTF-8'?>
<xs:schema
    xmlns:xs='http://www.w3.org/2001/XMLSchema'
    targetNamespace='http://www.xmpp.org/extensions/xep-0195.html#ns'
    xmlns='http://www.xmpp.org/extensions/xep-0195.html#ns'
    elementFormDefault='qualified'>
  <xs:element name='page'>
    <xs:complexType>
      <xs:sequence minOccurs='0'>
        <xs:element name='description' type='xs:string' minOccurs='0'/>
        <xs:element name='keywords' type='xs:string' minOccurs='0'/>
        <xs:element name='title' type='xs:string' minOccurs='0'/>
        <xs:element name='uri' type='xs:anyURI'/>
      </xs:sequence>
    </xs:complexType>
  </xs:element>
</xs:schema>
  1. XEP-0060: Publish-Subscribe <http://www.xmpp.org/extensions/xep-0060.html>.
2. XEP-0163: Personal Eventing via Pubsub <http://www.xmpp.org/extensions/xep-0163.html>.
3. XML Schema Part 2: Datatypes <http://www.w3.org/TR/xmlschema-2/>.
4. The Internet Assigned Numbers Authority (IANA) is the central coordinator for the assignment of unique parameter values for Internet protocols, such as port numbers and URI schemes. For further information, see <http://www.iana.org/>.
5. The XMPP Registrar maintains a list of reserved protocol namespaces as well as registries of parameters used in the context of XMPP extension protocols approved by the XMPP Standards Foundation. For further information, see <http://www.xmpp.org/registrar/>.
6. XEP-0053: XMPP Registrar Function <http://www.xmpp.org/extensions/xep-0053.html>.
Updated in accordance with XEP-0163.
(psa)Initial version.
(psa)First draft.
(psa)END