Silence Suppression On Full-Duplex Links - Nortel BCM50 Configuration Manual

The effect of silence suppression on half-duplex links is, therefore, to reduce the peak and average
bandwidth requirements by approximately 50% of the full transmission rate. Because the sender
and receiver are sharing the same bandwidth, this effect can be aggregated for a number of calls.
The following figure shows the peak bandwidth requirements for two calls on a half-duplex link
with silence suppression enabled. The peak bandwidth for all calls is equal to the sum of the peak
bandwidth for each individual call. In this case, that is twice the full transmission rate for the two
calls.
Figure 148 Two calls on a half-duplex link with silence suppression
Conversation
Tx
Rx
Hola Isabella
Tx
Rx
Fred here.
Conversation
Bandwidth used
Peak channel bandwidth is n * average
bandwidth per call

Silence suppression on full-duplex links

On full-duplex links, the transmit path and the receive path are separate channels, with bandwidths
usually quoted in terms of individual channels. The following figure shows the peak bandwidth
requirements for one call on a full-duplex link without silence suppression. Voice packets are
transmitted, even when a speaker is silent. Therefore, the peak bandwidth and the average
bandwidth used equals the full transmission rate for both the transmit and the receive channel.
Buenos noches Juan
Hello Fred. This is Susan.
Appendix B Silence suppression
Muy bien, y tu?
Com o esta?
Do you have a minute?
Hi!
Bandwidth shared by half-duplex calls
Networking Configuration Guide
531
Sure!
Channel/Link max
Time