Which protocol enables VCS-C system to be discovered by Cisco TMS?

HTTP is a web transfer protocol used for management interfaces, not for TMS device discovery.

CDP operates at Layer 2 between directly connected Cisco devices and is not used by TMS for endpoint discovery.

SOAP is an XML-based web services messaging protocol, not a discovery protocol used by TMS.

Cisco TMS relies on SNMP to discover VCS (Video Communication Server) devices. TMS polls devices via SNMP to retrieve system information, status, and configuration data, making SNMP the required protocol for the TMS device discovery process.

XMPP is an instant messaging and presence protocol unrelated to TMS device discovery.