XEP-0195: User Browsing

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.

Document Information

Author Information

Peter Saint-Andre

Email: stpeter@jabber.org
JabberID: stpeter@jabber.org

Legal Notice

Discussion Venue

Relation to XMPP

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.

Conformance Terms

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

1. Introduction

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).

2. Protocol

2.1 Container Element and Child Elements

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://jabber.org/protocol/browsing' namespace. The web page information itself is provided as the XML character data of the following children of the <page/> element:

Table 1: Child Elements

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 title of the web page (i.e., value of the <title/> element)	one small voice	xs:string	OPTIONAL
uri	The URI of the page (usually but not necessarily an HTTP URL)	http://www.saint-andre.com/blog/	xs:anyURI	REQUIRED

NOTE: The datatypes specified above are defined in XML Schema Part 2 [3].

2.2 Transport Mechanism

When a user visits a web page, its client may publish that fact to a special pubsub or PEP node (if a PEP node, the NodeID is "http://jabber.org/protocol/browsing"). The web page information SHOULD be communicated and transported by means of the XEP-0060 protocol, especially the subset specified in XEP-0163 (as shown in the following examples). 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://jabber.org/protocol/browsing'>
      <item id='da6abe63d1e5ed45a6de466732abff72e6fccb93'>
        <page xmlns='http://jabber.org/protocol/browsing'>
          <uri>http://www.saint-andre.com/blog/</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://jabber.org/protocol/browsing'>
      <item id='da6abe63d1e5ed45a6de466732abff72e6fccb93'>
        <page xmlns='http://jabber.org/protocol/browsing'>
          <uri>http://www.saint-andre.com/blog/</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 to the node 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://jabber.org/protocol/browsing'>
      <item id='da6abe63d1e5ed45a6de466732abff72e6fccb93'>
        <page xmlns='http://jabber.org/protocol/browsing'/>
      </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://jabber.org/protocol/browsing'>
      <item id='da6abe63d1e5ed45a6de466732abff72e6fccb93'>
        <page xmlns='http://jabber.org/protocol/browsing'/>
      </item>
    </items>
  </event>
</message>
.
.
.

3. Security Considerations

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).

4. IANA Considerations

This document requires no interaction with the Internet Assigned Numbers Authority (IANA) [4].

5. XMPP Registrar Considerations

5.1 Protocol Namespaces

The XMPP Registrar [5] shall include 'http://jabber.org/protocol/browsing' in its registry of protocol namespaces.

6. XML Schema

<?xml version='1.0' encoding='UTF-8'?>

<xs:schema
    xmlns:xs='http://www.w3.org/2001/XMLSchema'
    targetNamespace='http://jabber.org/protocol/browsing'
    xmlns='http://jabber.org/protocol/browsing'
    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>

Notes

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/>.