SipX

articleissues
article=yes
notability=January 2008
advert=December 2007
unreferenced=January 2008

Infobox_Software
name = SIPfoundry sipX ECS (IP PBX)



caption = Screenshot of the sipX Configuration Manager
developer = SIPfoundry
latest_release_version = 3.10.2
latest_release_date = July 23 2008
operating_system = Linux FreeBSD
genre = IP telephony
license = GNU Lesser General Public License
website = http://www.sipfoundry.org/

sipX ECS (Enterprise Communications Server) is an open source voice over IP telephony server [cite web
url= http://www.nilando.de/
title= Germany based company Nilando offers a sipX based appliance|accessdate=2008-03-20
format= HTML
quote= Die Nilando VoIP Appliance ist eine auf dem Open Source Projekt sipX basierende IP-Telefonanlage.] . Its main feature is a software implementation of the Session Initiation Protocol (SIP), which makes it an IP based communications system (IP PBX). Featurewise, it is not unlike Asterisk, a very popular open source PBX, but the design of sipX deviates from Asterisk in many ways. Development started in 1999, but in 2004 Pingtel Corp contributed the codebase to the non-profit organization SIPfoundry. It is an open source project since then. sipX is available under the GNU Lesser General Public License (LGPL) as well as a commercial offering from Pingtel Corp under the name Sipxchange. Another commercial offering comes from the German Company Nilando [cite web
url= http://www.voip-news.com/feature/essential-guide-open-source-voip-031208/
title= The Essential Guide to Open-Source VoIP - VoIP News|accessdate=2008-03-13
format= HTML
quote= SipX is an open-source VoIP telephony server.] Its software platform is Linux and FreeBSD

sipX includes many features of a traditional private branch exchange (PBX) like voice mail, interactive voice response systems, auto attendants and the like. Furthermore it integrates with Exchange 2007 [cite web
url= http://blog.lithiumblue.com/2007/04/accessing-exchange-2007-unified_29.html
title= Accessing Exchange 2007 Unified Messaging: Introduction|accessdate=2008-03-20
format= HTML ] and Active Directory Environments.

The main components of the system is a SIP switch or router around which sipX is designed. In contrast to its main open source competitor Asterisk PBX and most commercial offerings that use SIP as a transport protocol, SipX doesn't play the role of a back-to-back user agent. This approach led to a modular and highly scalable system. All major components of sipX are implemented as servers and do not necessarily have to reside on a single machine only. Distributed installations are known.

Design philosophy

sipX is distinguished from most other open source VoIP PBXs by several characteristics:
* All call signaling is handled using the SIP protocol natively (vs. gatewaying SIP to some other signaling protocol, e.g. as done in the Asterisk PBX).
* The sipX components handle call signaling, but once a call is set up, the voice (media) packets are sent directly between the endpoints involved. This allows most of the sipX components to be agnostic about the media and its encodings. E.g., SIP-based Videophones can communicate without increasing the load on the sipX system.
* The architecture of the system is client-server based and non-monolithic; the sipX components (proxy, media server, etc.) communicate between each other via the SIP protocol and can be run on different hosts (or replaced with other SIP components).
* The system administrative interface is web-based (vs. a command-line interface) and named sipXconfig.

sipX adheres to the SIP philosophy of implementing many features with significant support in the endpoints (telephones, gateways, voicemail systems) rather than entirely in the core components (proxy). This improves scalability but makes many features dependent on support in the endpoints of the telephone system.

Applications

sipX ECS is used by small and large enterprises ranging up to about 10,000 users. The largest publicly announced deployment is at Amazon.com using a high-availabity installation serving over 5,000 users ( [http://www.pingtel.com/page.php?id=70&view=122 announced October 6, 2006] ).

Availability

sipX is available on multiple platforms like FreeBSD and major Linux distributions, including Red Hat Enterprise Linux, Fedora Core, CentOS, Debian and others. Beginning with version 3.10 sipX does have native support for PowerPC (big endian) systems. Installation packages are available as well as modified ISO images of complete distributions with easy to use installation routines for sipX.

Hardware

sipX supports the use of Ethernet-attached SIP hardware and also software phones. sipX itself does not interface to traditional phone lines. To attach ordinary (non-VoIP) phones or PSTN lines to the PBX, IP/PSTN gateways have to be used. sipX supports a number of commercially-available gateways. A list of supported hardware can be found at [http://www.voip-info.org/wiki/view/sipX Voip Info Wiki]

Side Notes

* In addition to the above mentioned, the sipX ECS system serves as a reference implementation of the SIP standard. It is used at SIPIT interoperability events organized by the SIP Forum to test interoperability of SIP solutions from many different vendors.
* An automated SIP interoperability portal based on sipX is provided for free by Pingtel Corp. It is primarily used by SIP phone manufacturers for SIP compliance and advanced feature testing.

External links

* [http://www.sipfoundry.org/sipX Official website]
* [http://www.voipplanet.com/backgrounders/article.php/3660766 Installation guide]
* [http://www.voipplanet.com/backgrounders/article.php/3668051 sipX Tools for the command line]

References