Avaya DEFINITY Server CSI Maintenance Manual page 119

Multimedia Call Handling
Solution
In the first type described above, wiring problems, power to the camera, or video
encoder circuit pack problems in the codec are typical causes.
In the second type, no video from an endpoint typically occurs because it is not a
valid video source. This can be checked by looking at page 1 of the Status
Conference x Endpoint y Vid screen under the Capability section. In this section, a
"y" or "c" suggests that the endpoint has video. An "e" means ept has not declared
any video capability in cap set, "n" is audio only, and "blank" means audio add-on.
Also check page 1 of the Status Conference x Endpoint y Vs screen for indication
of the video state for the endpoint values.
Calls Terminate Correctly but Are Unstable
Description
A number of conditions will lead to some or all endpoints having stability problems
during the course of a conference. A lack of stability from an endpoint is
noticeable by a lack of a video switching while the party is the only talker or
excessive disconnects from that endpoint.
Synchronization
Generally, the most common problem is a mismatch in synchronization sources
between the endpoint and the Avaya Definity Server CSI MMCH. This typically
causes low-level (Px64) handshake problems that can trigger the endpoint/MMCH
to disconnect the call. The MCCH's timers are set to sufficiently high values so
that, normally, the endpoint will timeout and disconnect first. If installed in a
customer network, it is a good idea to perform an audit of the path synchronization
is being supplied. If there are different clock sources between endpoints and the
Avaya Definity Server CSI MMCH, some problems are sure to occur. The severity
of these problems can range from a handshake failure every few seconds to one
per day. Depending on the type of endpoint, this can cause the endpoint to
disconnect or just freeze video until the main problem is resolved.
Specifically, PictureTel System 4000 endpoints seem to be the most sensitive to
instability. The Vistium also disconnects fairly infrequently. Last, the CLI
Rembrandt II VP freezes video and waits for framing to be recovered.
555-233-119 Issue 5 October 2002
119