E V E R Y C A L L C O U N T S
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SETTING CODEC OPTIONS
If you are using an approved VoIP service provider, visit the support website at
http://
global.talkswitch.com
to access the service configuration guide for your VoIP service provider. The
service configuration guide lists supported codecs.
A codec is a method of compressing and decompressing audio signals for communication across a
network. The system supports the G.729 and G.711 (µ-law or A-law) codecs for VoIP calls. If your
service provider or equipment requires specific codecs for VoIP or Fax over IP calls, you can restrict
the system to use the required codec.
The
Codec Options
window allows you to select the codecs that your system can use, specify the
preferred codec, and clear the unsupported codecs. You can specify the codecs for the multi-branch
profile, and for each service provider profile. External IP extensions will use the preferred codec
specified in the multi-branch profile.
1. Select the
VoIP Configuration
page.
2. Click
Codec Options
. The
Codec Options
window appears.
3. Select the codecs that your system can use, and clear the unsupported codecs. The following
codecs are supported:
•
G.729
— This codec provides good quality. It requires the least bandwidth and accommodates
the highest number of concurrent calls.
•
G.711
µ — This codec provides high quality and supports Fax over IP. It requires the most
bandwidth and accommodates the fewest number of concurrent calls. G.711µ is used in North
America and Japan.
•
G.711A
— This codec provides high quality and supports Fax over IP. It requires the most
bandwidth and accommodates the fewest number of concurrent calls.
G.711A is used
worldwide except for North America and Japan.
4. Select the
Preferred codec
.
G.729
is the default codec, which uses the least bandwidth and
accommodates the highest number of concurrent calls.
5. Set
Voice activity detection (VAD)
. Enabling VAD reduces voice bandwidth when no speech is
detected, and reduces transmission of background noise. We recommend disabling VAD to keep
bandwidth available for speech.
