Administrator’s Guide for Yealink Video Conferencing Systems2SIPSIP (Session Initiation Protocol) is the Internet Engineering Task Force’s (IETF’s) standard formultimedia conferencing over IP. It is an ASCII-based, application-layer control protocol(defined in RFC 3261) that can be used to establish, maintain, and terminate calls between twoor more system. Like other VoIP protocols, SIP is designed to address the functions of signalingand session management within a packet telephony network. Signaling allows call informationto be carried across network boundaries. Session management provides the ability to controlthe attributes of an end-to-end call.Physical FeaturesVideo conferencing systems are in the overall network topology, which are designed tointeroperate with other compatible equipment, including application servers, media servers,Internet-working gateways, and other systems.In order to operate systems in your network successfully, the systems must meet the followingrequirements: A working IP network is established. VoIP gateway is configured for SIP or H.323, and H.323 gatekeeper is configured for H.323.You can also deploy Cloud server for Cloud platform. The latest (or compatible) firmware of system is available. A call server is active and configured to receive and send SIP/H.323 messages.The VC400 and the VC120 have same physical interfaces, camera parameters and videoresolutions.VC400/VC120 Codec Interface- 2 x HDMI- 1x DVI- 1x VGA- 1xVCS phone port(RJ-45)- 1x10/100/1000M Ethernet- 1 x Line-in (3.5mm)- 1 x Line-out (3.5mm)- 2 x USB2.0 port- 1 x power port- Others: 1 x power key, 1 x security lock slot, 1 x reset slot