Codec profiles 85
G.729AB
The G.729AB codec is the default preferred codec when adding a new IP
Trunk3.01 (and later) node in TM 3.1. This codec provides near toll-quality
voice at a low delay.The G.729AB codec uses compression at 8 kbit/s (8:1
compression rate). Optional B Voice Activity Detection/Silence Suppression
is configurable through TM 3.1. An ITG-Pentium 24-port trunk card suppor ts
24 channels per card with G.729AB. A Media Card 32-port trunk card
supports 32 channels per card with G.729AB.
G.729BThe G.729B codec uses compression at 8 kbit/s (8:1 compression rate).
Optional B Voice Activity Detection/Silence Suppression is configurable
through TM 3.1. An ITG-Pentium 24-port trunk card supports only 16
channels per card with G.729B due to higher DSP resources required for
this codec. The Media Card 32-port trunk card does not suppor t G.729B.
G.723.1 (5.3 kbit/s or 6.3 kbit/s)
The G.723.1 codec provides the greatest compression. Voice Activity
Detection/Silence Suppression is configurable through TM 3.1. An
ITG-Pentium 24-port trunk card supports 24 channels per card with
G.723.1. A Media Card 32-port tr unk card supports 32 channels per card
with G.723.1.
Three downloadable DSP profiles support the codecs shown in Tab le 9
"Codecs supported by IP Trunk 3.01 (and later)" (page 85).
Tabl e 9
Codecs supported by IP Trunk3.01 (and later)
Profile 1
32 ms. Echo Cancel Tail
24 ports/card for ITG-P
24-port card
32 ports/card for SMC
32-port card
Profile 2
32 ms. Echo Cancel Tail
24 ports/card for ITG-P
24-port card
32 ports/card for SMC
32-port card
Profile 3
32 ms. Echo Cancel Tail
16 ports/card for ITG-P
24-port card
Not supported for SMC
32-port card
PCM A-law (G.711) PCM A-law (G.711) PCM A-law (G.711)
PCM µ-law (G.711) PCM µ-law (G.711) PCM µ-law (G.711)
G.729AB G.723.1 5.3 kbit/s G.729B
Clear Channel G.723.1 6.3 kbit/s Clear Channel
Fax Clear Channel Fax
Fax
Each codec supports one of three sets of parameters: one for DSP, one
for fax, and one forcodec.
Nortel Communication Server 1000
IP TrunkFundamentals
NN43001-563 02.01 Standard
Release 5.5 21December 2007
Copyright© 2007, Nor tel Networks
.