5.37.1.1. Task of the Feature 
The feature Voice Compression (VC) increases the capacity of speech
channels on S0/S2 trunks.
|
B-channels without VC
|
speech channels with VC
|
|
|
per S0 trunk
|
2
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up to 7
|
|
per S2 trunk
|
30
|
up to 112
|
If a S0/S2 B-channel is configured for VC, it can only be used for
voice communication. Therefore it is possible to use only some and not
all B-channels of a S0/S2 circuit by VC.
From ATM level 3 an STMA circuit can be a partner circuit, provided
the STMA board is configured as "STMA networking 1.0 (=backboning, ATMPBB)''
or as STMA networking 2.0 (=Networking 2.0, ATMNW20). With operating
mode "ATMNW20" only ATMPVCxx circuits should be configured, as ATMSVC
circuits do not support the required functions.
Other STMA functions for this feature have not yet been released .
An STMA circuit handles like an S2 circuit and will not be described
in detail.