Which protocol does the Cisco TelePresence Content Server use for call signaling?

MGCP is a protocol for controlling media gateways from an external call agent and is not used for endpoint call signaling on the TelePresence Content Server.

Cisco does not use a proprietary signaling protocol for the TCS; it relies on the industry-standard H.323 protocol for interoperability.

SCCP (Skinny Client Control Protocol) is Cisco's proprietary protocol used by Cisco IP phones to communicate with Cisco Unified Communications Manager, not for TelePresence Content Server call signaling.

H.323 is an ITU-T standard for multimedia communication over packet-based networks and is the primary call signaling protocol supported by the Cisco TelePresence Content Server. TCS uses H.323 to register with gatekeepers and receive calls for recording or streaming. This standard protocol ensures interoperability with a broad range of video conferencing endpoints and infrastructure.