Avaya DEFINITY Server CSI Maintenance Manual page 120

Maintenance for CSI systems
Network Configuration Concerns with Synchronization
When auditing a network for synchronization, avoid unnecessary hops. Thus, a
switch providing star-configuration synchronization is preferred over a daisy-chain
configuration. Additionally, if there are Avaya Definity Server CSI systems that
have EPNs, synchronization should be provided to sub nodes from the same port
network through which the PBX receives its synchronization. Passing
synchronization through the PBX Expansion Interface adds an unnecessary hop
to the path and creates another potential point of failure.
Expansion Interface Duplication
If a customer's network uses PBX EPNs with duplicated Expansion Interfaces,
scheduled switching of the Expansion Interface links should be disabled on the
PBX via change system-parameters maintenance. When scheduled
maintenance runs and switches the links, there is a brief corruption of the data
path. If endpoints have active calls when the switch occurs, this corruption of the
data path causes Px64 handshake problems, which lead to the endpoints losing
video source status, and sometimes disconnecting as described above. Disabling
the EI switching is in the customer's best interest to prevent the disruption of the
Px64 data stream. The customer will get the same level of alarm indications and
maintenance on the EI links, regardless of the status of scheduled switching.
PRI D-Channel Backup
A somewhat unlikely source of call stability problems occur where the translations
for PRI D-channel Backup between two non-MCU switches were incorrect. As an
example, on switch A, DS1 1A10 was designated as the primary source, and on
switch B, the corresponding DS1 was designated as the secondary source. When
scheduled maintenance was run on the switch that had an active standby
D-channel, an audit disconnected some calls using the link. The problem was
corrected when the D-channel primary/secondary assignments matched.
Processor Duplication on the PBX
Do not enable the PI link switch on scheduled maintenance. This can cause link
stability problems on the Accunet Bandwidth Controller (ABC).
Voice-Activated Switching Problems
Voice-activated switching on the Avaya Definity Server CSI MMCH does not
follow the loudest talker. The MMCH queues all speaking parties and selects a
new video broadcaster (the second-oldest speaking party) when the oldest
speaking party has stopped talking. The new broadcaster sees the last speaker
as its video. The system can also "learn" about the noise coming from an endpoint
to help prevent false switches, adapting both to noise level and repetitive sounds
such as a fan. This adaptation occurs over approximately 10 seconds.
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Issue 5 October 2002
555-233-119