Dynamic Call Admission Control (Cac); Enabling Dynamic Cac On The G250/G350; Using Dynamic Cac On The Mgc - Avaya G250 Maintenance Manual

Dynamic Call Admission Control (CAC)

In order to manage the flow of calls and voice data on the G250/G350 most efficiently, the
Media Gateway Controller must have real-time information about the network topology and
currently available bandwidth. Without this, changes to the network structure, such as switching
over to a backup line, can cause the network to become overloaded with voice data. The MGC,
unaware of the switchover, continues to admit calls at the same volume, causing network
congestion. Using the Dynamic Call Admission Control (CAC) feature, the G250/G350 can
provide the MGC with up-to-date information on the bandwidth available for voice data.
By default, G250/G350 interfaces do not participate in Dynamic CAC. However, it is highly
recommended to enable Dynamic CAC on the G250/G350's interfaces. If users report problems
with long delays, jitter, and loss of calls, enable Dynamic CAC to provide greater link reliability
and robustness.

Enabling Dynamic CAC on the G250/G350

Use the dynamic-cac command to enable Dynamic CAC on the G250/G350. Dynamic CAC
must be enabled on each interface responsible for providing call bandwidth. If Dynamic CAC is
enabled on more than one interface, specify an activation priority for each interface. The BBL
(Bearer Bandwidth Limit) is reported as the BBL of the interface with the highest activation
priority.
The dynamic-cac command has the following syntax:
dynamic-cac bbl [activation-priority]

Using Dynamic CAC on the MGC

Use the change ip-network-region SAT command to mark direct connections among
regions as ":Dynamic", and specify which media gateway is responsible for setting dynamic
CAC updates for that link.
Use the status ip-network-region SAT command to view the current dynamic bandwidth
value.
Dynamic Call Admission Control (CAC)
Issue 1.1 June 2005 63