World Library  
Flag as Inappropriate
Email this Article

Skinny Call Control Protocol

Article Id: WHEBN0000100083
Reproduction Date:

Title: Skinny Call Control Protocol  
Author: World Heritage Encyclopedia
Language: English
Subject: SCCP, Skinny, Signaling protocol, Cisco protocols, VoIP protocols
Publisher: World Heritage Encyclopedia

Skinny Call Control Protocol

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.[1][2] Examples of SCCP clients 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. CallManager acts as a signaling proxy for call events initiated over other common protocols such as H.323, Session Initiation Protocol (SIP), ISDN and/or MGCP.


  • Protocol components 1
  • Origin 2
  • Other implementations 3
  • See also 4
  • References 5
  • External links 6

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 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.


Cisco acquired SCCP technology when it acquired Selsius Corporation in 1998.[3] 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.

Other implementations

Other companies, such as Symbol Technologies, SocketIP, and Digium, have implemented the protocol in VoIP terminals and IP phones, media gateway controllers, and softswitches. An open source implementation is available in the Asterisk and FreeSWITCH systems.[4] IPBlue provides a soft phone that emulates a Cisco 7960 telephone.[5] Twinlights Software distributes a soft phone implementation for Android-based devices.[6] 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


  1. ^ Understanding IP Telephony Protocols
  2. ^ Call states sent to SCCP endpoints by Cisco CallManager
  3. ^ Cisco Systems acquisition of Selsius Systems (
  4. ^
  5. ^ IPBlue
  6. ^ Twinlights Software

External links

  • Skinny Call Control Protocol (SCCP) - Cisco Systems
  • Skinny Call Control Protocol (SCCP) - Fragment of a VoIP course dealing with SCCP, with sample captures
  • Alternative SCCP channel driver for Asterisk. Sourceforge Project called chan-sccp-b
This article was sourced from Creative Commons Attribution-ShareAlike License; additional terms may apply. World Heritage Encyclopedia content is assembled from numerous content providers, Open Access Publishing, and in compliance with The Fair Access to Science and Technology Research Act (FASTR), Wikimedia Foundation, Inc., Public Library of Science, The Encyclopedia of Life, Open Book Publishers (OBP), PubMed, U.S. National Library of Medicine, National Center for Biotechnology Information, U.S. National Library of Medicine, National Institutes of Health (NIH), U.S. Department of Health & Human Services, and, which sources content from all federal, state, local, tribal, and territorial government publication portals (.gov, .mil, .edu). Funding for and content contributors is made possible from the U.S. Congress, E-Government Act of 2002.
Crowd sourced content that is contributed to World Heritage Encyclopedia is peer reviewed and edited by our editorial staff to ensure quality scholarly research articles.
By using this site, you agree to the Terms of Use and Privacy Policy. World Heritage Encyclopedia™ is a registered trademark of the World Public Library Association, a non-profit organization.

Copyright © World Library Foundation. All rights reserved. eBooks from Project Gutenberg are sponsored by the World Library Foundation,
a 501c(4) Member's Support Non-Profit Organization, and is NOT affiliated with any governmental agency or department.