Which endpoint transport is the default when configuring Cisco TelePresence Server?

SIP is a signaling protocol, not a transport - it runs over a transport such as TCP or UDP, so it is not a valid answer to a question asking which transport is the default.

SCCP (Skinny Client Control Protocol) is a Cisco proprietary call control protocol used with IP phones and is not the default or common protocol used for Cisco TelePresence Server endpoint configuration.

Cisco TelePresence Server uses TCP as the default transport protocol for endpoint connections because TCP provides reliable, ordered delivery that is required for SIP signaling and control traffic. The administrator can change this to another transport, but TCP is the out-of-box default when adding endpoints to TelePresence Server.

UDP is a valid transport option for SIP-based signaling but is not the default transport selected when configuring endpoints on Cisco TelePresence Server.