Codecs Page 293 of 910
IP Line Description, Installation and Maintenance
Example 2
A user configures four codecs:
1G.711 a-law codec with a 10 msec payload
2G.729A codec with 50 msec payload
3G.729AB codec with 30 msec payload
4G.723.1 codec with a 30 msec payload
The following five codecs are actually registered:
1G.711 a-law (10 msec)
2G.711 mu-law (10 msec)
3G.729A (50 msec)
4G.729AB (30 msec)
5G.723.1 (30 msec)

Codec registration for DSPs

DSPs register the following codecs:
• both G.711 a-law and G.711 mu-law codecs are always registered
• both fax codecs (T.38 and G.711 Clear Channel) are always registered
• one best bandwidth (BB) codec, if at least one of G.729A, G.729AB, or
G.723.1 codecs was configured. The BB codec is based on the codec
type. The order of preference for choosing the BB codec is G.729AB,
G.729A, and then G.723.1.
IMPORTANT!
When G.723.1 codec is configured on the Media Card 32-port line card,
the number of channels is reduced to 24. This is a limitation of the DSP
software. The unused channels are not registered, therefore the Call
Server software does not access them