Support for XCAP in SIP Communicator

GSoC Student: Grigorii Balutsel - (Belarus)
Mentors: Werner Dittmann - Germany, Damian Minkov (Bulgaria), Emil Ivov (France/Bulgaria)\\

Project Requirements ( show )

First term:

  1. XCAP access utilities in impl.provider.sip.xcap
  2. Basic contact list retrieval through OperationSetPersistentPresence
  3. Automatic discovery policies for the default XCAP server associated with a SIP account

Second term:

  1. Authorization policies
  2. Retrieving images
  3. Update the SIP provider unit tests

As you probably know, most of the time services that support instant messaging and presence (such as Google Talk (XMPP), Facebook (again XMPP :) ), MSN, etc.) your buddies would be stored on a server somewhere on the network. This seems quite rational since it allows you to keep the same buddy list regardless of where using the service from. In all these cases SIP Communicator would also keep a local copy of all your contacts but only so that you could see them when offline, merge them and add extra details to them.

One exception to this rule is the SIP protocol. SIP has always been a great tool for doing Internet telephony but for some reason, it has always lagged a bit (both implementation and specification wise), as far as instant messaging and presence goes. As a result, in the case of SIP Communicator, even though we do support presence and allow users to add SIP buddies to their lists, it is impossible to retrieve them off of a server.

We have now decided it is high time we fixed this. A couple of years ago the IETF rolled out its XCAP specification .

Contrary to SIP, which has its own transport mechanisms and uses directly TCP and UDP, the XCAP protocol uses HTTP to connect to XCAP servers, and retrieve and manipulate contact/resource lists.

The purpose of this project is to implement support for this protocol in SIP Communicator so that SIP users would now be able to store and retrieve their SIP buddies from the network and keep them when they move from one workstation to another.

References:

The XML Configuration Access Protocol (XCAP) (RFC 4825)
http://tools.ietf.org/html/rfc4825

XML Formats for Representing Resource Lists (RFC 4826)
http://tools.ietf.org/html/rfc4826

The IETF SIMPLE Working Group
http://www.ietf.org/dyn/wg/charter/simple-charter.html

Other SIP Communicator GSoC Projects
http://gsoc.sip-communicator.org

SIP Communicator Developer Documentation
http://www.sip-communicator.org/index.php/Documentation/DeveloperDocumentation

The official SIP Communicator website
http://www.sip-communicator.org