Protocol H.323 introduces call signaling and control, multimedia transmission and management, and bandwidth control for point-to-point and multi-point conferences.
The H.323 protocol is divided into the following three control sections:
• RAS Protocol
• Media Control and Transport (H.245) Signaling
• Call Control/Call Setup (H.225)
• RAS Protocol
The RAS protocol is part of the H.323 Recommendation and is a protocol that uses H.323 between endpoints (terminals and gateways) and gatekeepers. The RAS protocol uses port UDP-1719.
The RAS channel is independent of the call and media transmission channel.
Comparison between SIP and H.323 protocols
