SIP SIMPLE Client SDK

= Developer guide =

<abbr title="WikiStart, Sip*, depth=2">TOC</abbr>

The main goal of this library is to provide a simple to use API to create real-time communications applications between end-points based on SIP protocol.

Prerequisites

To use the library and the concepts described below you must be familiar with Python programming language and basic SIP call flows from [http://www.tech-invite.com/Ti-sip-CF3665.html RFC 3665]. Understanding of TCP/IP networking and real time application development in general are strongly recommended.

Instructions for installing the library are found [wiki:SipInstallation here].

Middleware

To develop your application you should use the middleware API that hides the complexity and interactions of the lower level SIP, SDP, RTP, ICE, MSRP, XCAP and related protocols. With a minimal amount of coding you can create a client SIP application for setting up audio, instant messaging and desktop sharing sessions.

• [wiki:SipMiddlewareApi Middleware API] - event driven middleware suitable for developing interactive user interfaces (e.g. GUI)
• [wiki:SipSettingsAPI Settings API] - used to managing the settings used by the middleware

=== Sample code ===

The middleware API is used by the command line tools used for [wiki:SipTesting testing the library].

Components

To develop your own middleware or application while controlling the underlying protocol layers yourself, you can use the following APIs that provides granular control over their respective components:

• [wiki:SipCoreApiDocumentation SIP core API] - The API for the SIP, SDP, RTP, ICE and audio engine (cross platform sound-card abstraction, codecs)
• [wiki:SipMSRPApi MSRP API] - The API for Message Session Relay Protocol (MSRP) and its relay extension used for instant messaging, file transfers and desktop sharing applications
• [wiki:SipPresenceApi Presence API] - The API for payloads carried within SIP signaling used for publication, subscription and notifications of SIP events
• [wiki:SipXCAPApi XCAP API] - The API for XCAP document manipulation used for storage of buddy lists and presence policy documents

You may use for example the above components API to create a SIP application server.

Networking

To use a SIP application you need access to a TCP/IP network (e.g. the Internet). The library uses the following ports when active:

'''Local port'''

'''Direction'''

'''Remote port'''

'''Protocol'''

'''Description'''

'''Allocation'''

'''Setting'''

1x port >1024

In/Out

Typically 5060 set in DNS

UDP

SIP over UDP

At start

Global.sip.local_udp_port

1x port >1024

In/Out

Typically 5060 set in DNS

TCP

SIP over TCP

At start

Global.sip.local_tcp_port

1x port >1024

In/Out

Typically 5061 set in DNS

TCP

SIP over TLS

At start

Global.sip.local_tls_port

2x port >1024

In/Out

Random negotiated in SDP

UDP

RTP/RTCP stream

Per session

Global.rtp.port_range

1x port >1024

In/Out

Typically 2855 negotiated in SDP

TCP

MSRP stream

Per session

Global.msrp.local_port

1x port >1024

Out

Typically 443, statically provisioned

TCP

XCAP requests

Per request

Global.xcap.local_port