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MAS commissioning
SIP registrar servers
A SIP registrar server is a database that contains the location of all user agents within a domain. MAS registers its applications with all configured SIP registrars. Registration is optional based on MAS configuration. Digest authentication is supported.
Media conferencing
MAS supports multimedia conferencing for both audio and video streams. You can use one of the following conferencing algorithms: basic and premium.
Basic conferencing algorithm
The basic conferencing algorithm mixes the two audio streams with the highest energy and provides the mixed audio to the remaining participants. The two participants with the highest energy audio streams receive only the other active participant's audio so they do not hear themselves. The participant with the highest energy with of the two highest energy speakers is known as the primary active speaker. The other participant is the secondary active speaker. (The system continually monitors the energy of all participants in a conference, and using threshold algorithms, changes the conference focus point.)
When some or all of the participants in the conference have corresponding video streams, the video streams of the primary active speaker are replicated and sent to those participants. The primary and secondary speakers see only each other if they have
Premium conferencing algorithm
A more advanced conferencing algorithm (called premium conferencing) mixes up to four parties simultaneously. Each channel runs a voice activity detector (to determine speech versus background noise), an automatic gain control algorithm, and a dynamic jitter buffer with compaction and packet loss concealment. This algorithm is suitable for mixing large conferences.
Number of conferences and participants
MAS has no hard limitations on how many simultaneous conferences can exist on the system, or how many participants can be in each conference. The maximum number of participants in a single conference, without bridging multiple conferences together, is limited only by the capacity of the scaled system, which can vary based on hardware and the operating system.
Nortel Media Application Server 6.0 for AS 5300
Fundamentals
Release 6.0 03 June 2008
Copyright © 2008, Nortel Networks
