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] 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.