SIP SIMPLE client SDK
---------------------

Copyright (c) 2008-2010 AG Projects
http://ag-projects.com


Description
-----------

SIP SIMPLE client SDK is a Software Development Kit for development of Real
Time Applications based on SIP and related protocols for Audio, Instant
Messaging, File Transfers, Desktop Sharing and Presence. Other media types
can be easily added by using an extensible high-level API.

The software has undergone in the past years several interoperability tests
at SIPIT (http://www.sipit.net) and today is of industry strength quality.

The SIP stack is provided by PJSIP (http://www.pjsip.org)


Background
----------

SIP stands for 'Sessions Initiation Protocol', an IETF standard described by
RFC3261. SIP is an application-layer control protocol that can establish,
modify and terminate multimedia sessions such as Internet telephony calls
(VoIP). Media can be added to (and removed from) an existing session.

SIP allows the endpoints to negotiate and combine any type of session they
mutually understand like video, instant messaging (IM), file transfer,
desktop sharing and provides a generic event notification system with
real-time publications and subscriptions about state changes that can be
used for asynchronous services like presence, message waiting indicator and
busy line appearance.


Features
--------

The library has cross platform capabilities on Linux OS, Mac OSX (Leopard
and Snow Leopard) and Microsoft Windows.  The library should work with
minimal changes on any platform that supports C and Python development
environments.

To see SIP SIMPLE client SDK features in action you can try Blink from
http://icanblink.com

For an up to date status of the readiness for the features listed bellow
visit project web site.

General

 * Written in Python programming language
 * Non-blocking asynchronous engine
 * High level middleware
 * Configuration framework
 * TLS Security for signaling (SIP) and media (MSRP, XCAP)
 * Multiple SIP Accounts support
 * Multiple Media Types per Session (e.g. Audio + IM)
 * Trace capability for all underlying protocols
 * Failover for DNS lookups, SIP and MSRP routing
 * Supports re-INVITE for adding and removing media
 * Automatically handling if IP Address changes
 * Audio conference bridge
 * Wav player and recorder
 * Acoustic Echo Cancelation
 * Answering machine
 * Wide-band Internet codecs: Speex and G722
 * PSTN compatible codecs: G711, iLBC, GSM

Supported media

 * Audio (RTP/sRTP)
 * Instant Messaging (MSRP)
 * File Transfer (MSRP)
 * Desktop Sharing (VNC over MSRP)

All media types can be combined together in the same SIP session.


Normative References
--------------------

SIP Signaling

 * Session Initiation Protocol (RFC3261) 
 * Session Description Protocol (RFC4566)
 * An Offer/Answer Model with Session Description Protocol (RFC4566)

Address Resolution

 * RFC3263 next hop resolution lookup
 * Bonjour multicast DNS draft-lee-sip-dns-sd-uri-03

NAT Traversal

 * SIP Signaling: Symmetric Response Routing Symmetric media (RFC3581)
 * RTP media (Audio and Video): ICE, Interactive Connectivity Establishment
   (draft-ietf-mmusic-ice-19)
 * MSRP media (Instant Messaging and File Transfer): MSRP protocol relay
   extension (RFC4976)
  
Voice over IP

 * RTP, A Transport Protocol for Real-Time Applications (RFC3550)
 * Real Time Control Protocol (RTCP) attribute in Session Description
   Protocol (SDP) (RFC3605)
 * SRTP, The Secure Real-time Transport Protocol (RFC3711)
 * Generation and parsing of telephone-events payload in both RTP and SDP
   (RFC2833)

Instant Messaging

 * CPIM, Common Presence and Instant Messaging: (RFC3862)
 * Session Initiation Protocol (SIP) Extension for Instant Messaging
   (RFC3428)
 * MSRP Protocol (RFC4975)
 * Indication of Message Composition for Instant Messaging (RFC3994)
 * Message Summary Event Package (RFC3842)
 * File Transfer (RFC5547)

Desktop Sharing

 * Variation of draft-garcia-mmusic-sdp-collaboration-00 using RFB over MSRP

Conferencing

 * Conference Event Package (RFC4575)
 * A Framework for Conferencing with the Session Initiation Protocol (RFC4353)
 * SIP Call Control - Conferencing for User Agents (RFC4579)
 * MSRP ad-hoc multi-party chat sessions (draft-ietf-simple-chat-06) - roadmap

Presence

 * SIP Specific Event Notification (RFC3265)
 * SIP Extension for Event State Publication (RFC3903) 
 * PIDF: Presence Data Model (RFC3863, RFC3379, RFC4479)
 * Watcher-info Event Package (RFC3857, RFC3858)
 * Rich Presence Extensions to PIDF (RFC4480)
 * Contact Information Extension to PIDF (RFC4482)
 * User Agent Capability Extension to PIDF (RFC5196) 
 * XCAP Protocol (RFC4825)
 * Common Policy (RFC4745)
 * Presence Rules (RFC5025)
 * Resource Lists (RFC4826)
 * RLS Services (RFC4826)
 * PIDF manipulation (RFC4827)
 * XCAP Diff (RFC5874)
 * OMA Reference Release Definition for XDM v1.1 and Presence SIMPLE v1.1
   Implementation Guidelines
 * OMA XML  Document Management V1.1


Support
-------

The project is developed and supported by AG Projects. The support is
provided on a best-effort basis. "best-effort" means that we try to solve
the bugs you report or help fix your problems as soon as we can, subject to
available resources.

To request support you must use the mailing list available at

http://lists.ag-projects.com/mailman/listinfo/sipclient

Patches and bug reports must be submitted by opening a ticket at

http://sipsimpleclient.com/newticket

To open ticket please Register first.


Acknowledgments
---------------

SIP SIMPLE client SDK has been partly funded by the European Commission
under grant number FP7-IST-216217.