Editing Skinny Client Control Protocol

{{distinguish|Signalling Connection Control Part}}
The '''Skinny Client Control Protocol''' ('''SCCP''') is a proprietary network terminal control protocol originally developed by [[Selsius Systems]], which was acquired by [[Cisco Systems]] in 1998.

SCCP is a lightweight IP-based protocol for session signaling with Cisco Unified Communications Manager, formerly named ''CallManager''.<ref>{{cite web |url=http://www.cisco.com/en/US/docs/voice_ip_comm/cucm/admin/8_5_1/ccmsys/a08procl.pdf |archive-url=https://web.archive.org/web/20150711070711/http://www.cisco.com/en/US/docs/voice_ip_comm/cucm/admin/8_5_1/ccmsys/a08procl.pdf |archive-date=2015-07-11 |url-status=live|title=Understanding IP Telephony Protocols|publisher=}}</ref><ref>{{cite web|url=http://www.cisco.com/en/US/products/sw/voicesw/ps556/products_tech_note09186a0080624977.shtml|title=Call States Sent to SCCP Endpoints by Cisco CallManager|website=Cisco}}</ref> The protocol architecture is similar to the [[media gateway control protocol architecture]], in that is decomposes the function of media conversion in telecommunication for transmission via an [[Internet Protocol]] network into a relatively low-intelligence customer-premises device and a call agent implementation that controls the CPE via signaling commands. The call agent product is Cisco CallManager, which also performs as a signaling proxy for call events initiated over other common protocols such as [[H.323]], and [[Session Initiation Protocol]] (SIP) for [[voice over IP]], or [[ISDN]] for the [[public switched telephone network]].

==Protocol components==
An SCCP client uses [[TCP/IP]] to communicate with one or more Call Manager applications in a cluster. It uses the [[Real-time Transport Protocol]] (RTP) over [[User Datagram Protocol|UDP]]-transport  for the bearer traffic (real-time audio stream) with other '''Skinny''' clients or an H.323 terminal. SCCP is a stimulus-based protocol and is designed as a communications protocol for hardware endpoints and other embedded systems, with significant CPU and memory constraints.

Some Cisco analog media gateways, such as the VG248 gateway, register and communicate with Cisco Unified Communications Manager using SCCP.

==Origin==
Cisco acquired SCCP technology when it acquired Selsius Corporation in 1998.<ref>{{cite web|archiveurl=https://web.archive.org/web/20051109224815/http://newsroom.cisco.com/dlls/fspnisapi6d14.html|title=News @ Cisco: Cisco Systems to Acquire Selsius Systems, Inc. for $145 Million|archivedate=9 November 2005|publisher=|url=http://newsroom.cisco.com/dlls/fspnisapi6d14.html}}</ref> For this reason the protocol is also referred to in Cisco documentation as the Selsius Skinny Station Protocol. Another remnant of the origin of the Cisco IP phones is the default device name format for registered Cisco phones with CallManager. It is ''SEP'', as in ''Selsius Ethernet Phone'', followed by the [[MAC address]]. Cisco also has marketed a Skinny-based softphone called Cisco IP Communicator.

==Client examples==
[[File:Cisco CP7970.jpg|thumb|Cisco 7970]]
Examples of SCCP client devices include the Cisco 7900 series of IP phones, Cisco IP Communicator softphone, and the [[802.11b]] wireless Wireless IP Phone 7920, along with Cisco Unity voicemail server.

==Other implementations==
[[File:Cisco CP7911 Asterisk connected.jpg|thumb|[[Asterisk]] connected]]

Other companies, such as [[Symbol Technologies]], SocketIP, and [[Digium]], have implemented the protocol in  VoIP terminals and IP phones, [[media gateway controller]]s, and [[softswitch]]es. An open source implementation of a call agent is available in the [[Asterisk (PBX)|Asterisk]] and [[FreeSWITCH]] systems.<ref>{{cite web|url=http://wiki.freeswitch.org/wiki/Mod_skinny|title=mod_skinny - FreeSWITCH - Confluence|website=wiki.freeswitch.org}}</ref> IPBlue provides a [[soft phone]] that emulates a Cisco 7960 telephone.<ref>http://www.ipblue.com/ IPBlue</ref>  Twinlights Software distributes a soft phone implementation for [[Android (operating system)|Android]]-based devices.<ref>http://www.twinlightssoftware.com/ Twinlights Software</ref> The Cisco Unified Application Environment, the product acquired by Cisco when they purchased [[Metreos]], supports using SCCP to emulate Cisco 7960 phones allowing applications to access all Cisco line-side features.

==See also==
*[[Media Gateway Control Protocol]]

==References==
{{Reflist}}

[[Category:VoIP protocols]]
[[Category:Cisco protocols]]
[[Category:Application layer protocols]]