SIP proxy Last modified: Wednesday, May 21, 2008
Also called a SIP server or SIP proxy server, in telecommunications it is one of the main components of an IP PBX that is used by SIP to perform many of the call set-up functions.  As described in RFC 3621 - SIP: Session Initiation Protocol SIP makes use of elements, called proxy servers (SIP proxy) "to route requests to the user's current location, authenticate and authorize users for services, implement provider call-routing policies, and provide features to users". Within the SIP network the SIP proxy actually manages the setup of calls between SIP devices including the controlling of call routing and it also performs necessary functions such as registration, authorization, network access control and in some cases it also handles network security. See Session Initiation Protocol (SIP). See also "Understanding SIP Part V: SIP Signaling" on Enterprise VoIP Planet. Also see "VoIP and the Small Business" in the "Did You Know..." section of Webopedia. Also see "Internet Telephony" in the Quick Reference section of Webopedia.
•E-mail this definition to a colleague• Sponsored listings Enterprise IP Telephony Guide - Free 96 page Enterprise IP Telephony eBook. 11 Chapters for decision makers helps you plan, implement, and deploy an IP telephony system. Learn More! Cisco Network Security - Online seller of refurbished Sun Microsystems, Cisco, Juniper, and F5 networks hardware offers Cisco network security. For internet.com pages about SIP proxy . Also check out the following links! Enterprise VoIP Planet  The IT Manager's Guide to Voice over IP RFC 3261 SIP: Session Initiation Protocol  This document describes Session Initiation Protocol (SIP), an application-layer control (signaling) protocol for creating, modifying, and terminating sessions with one or more participants. These sessions include Internet telephone calls, multimedia distribution, and multimedia conferences. Securing VoIP Networks, Part 1  SBCs are network elements that are deployed at the border between packet-based networks to manage the signaling and media messages that support Internet multimedia services (for example, voice or video). For example, they can be placed between service providers in a peering configuration or in an access network that provides VoIP service to residential or enterprise customers. Understanding H.323.Part III: Signaling  Two standards are involved with H.323 signaling: H.225.0, Call Signaling Protocols and Media Stream Packetization for Packet-based Multimedia Communication Systems; and H.245, Control Protocol for Multimedia Communications, both of which are available from the ITU Web site. Webopedia's Quick Reference Section  Use this Webopedia reference section for information on common Internet and computer facts and occurrences.	Internet Protocols Telecommunications interoperability IP PBX jitter jitter buffer presence proxy proxy server QoE QoS SIP SIP B SIPphone VoIP Give Us Your Feedback Shopping SIP proxy Products Compare Products,Prices and Stores Shop by Category: Phones 1 Model Matches IP Phones 2 Store Offers