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 SIP call flows from [http://www.tech-invite.com/Ti-sip-CF3665.html RFC 3665]. Understanding of TCP/IP networking in general and real time application development in particular 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 is event-driven, non-blocking and hides the complexity and the interactions of the lower level SIP, SDP, RTP, ICE, MSRP, XCAP and related protocols.
With a minimal amount of coding you can create a rich client application for setting up audio, instant messaging, file transfer and desktop sharing sessions.

• [wiki:SipMiddlewareApi Middleware API] - middleware suitable for developing interactive user interfaces (e.g. GUI)
• [wiki:SipConfigurationAPI Configuration API] - used for 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]. The command line tools are the best example for how to use the library.

Components

If you wish to develop your own middleware and/or application while having control over the underlying protocol layers yourself, you can use the following APIs that provides granular control over their respective components:

• [wiki:SipSessionApi Session API] - The high-level API for SIP sessions
• [wiki:SipStreamsApi Streams API] - The high-level API for Media Streams (RTP and MSRP)
• [wiki:SipPresenceApi Presence API] - The API for payloads carried within SIP signaling used for publication, subscription and notifications of SIP events
• [wiki:SipCoreApiDocumentation SIP Core API] - The low-level API for the SIP, RTP, ICE and audio engine (cross platform sound-card abstraction, codecs)
• [wiki:SipMSRPApi MSRP API] - The low-level API for Message Session Relay Protocol (MSRP) and its relay extension
• [wiki:SipXCAPApi XCAP API] - The low-level 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, something the high level middleware was not designed for.

TCP/IP ports

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'''

1xport >1024

In/Out

Typically 5060 set in DNS

UDP

[wiki:SipCoreApiDocumentation#Engine SIP over UDP]

At start

Global.sip.local_udp_port

1xport >1024

In/Out

Typically 5060 set in DNS

TCP

[wiki:SipCoreApiDocumentation#Engine SIP over TCP]

At start

Global.sip.local_tcp_port

1xport >1024

In/Out

Typically 5061 set in DNS

TCP

[wiki:SipCoreApiDocumentation#Engine SIP over TLS]

At start

Global.sip.local_tls_port

2xport >1024

In/Out

Random negotiated in SDP

UDP

[wiki:SipCoreApiDocumentation#RTPTransport RTP/RTCP stream]

Per session

Global.rtp.port_range

1xport >1024

In/Out

Typically 2855 negotiated in SDP

TCP

[wiki:SipMSRPApi#transport.MSRPTransport MSRP stream]

Per session

Global.msrp.local_port

1xport >1024

Out

Typically 443, configured

TCP

[wiki:SipXCAPApi XCAP requests]

Per request