Voice Activity Detection (Vad); Media Gateway (Mgw); Software Mgw - Aastra OpenCom 100 Series Mounting And Commissioning User Manual

Voice over IP (VoIP)

Voice Activity Detection (VAD)

You can change the codec configuration under Telephony: Extended: VoIP profile.
You can also activate the Voice Activity Detection option for one or more codecs in
so doing. If this option is active then pauses in the conversation will be replaced with
empty packets. This can be better compressed by compression-codecs thus reducing
the required bandwidth. This option must be deactivated if you want to assign the
profile to a SIP trunk and if you have set the G.711 codec.
Note
If you want to allocate the VoIP profile to an Aastra 675xi or Aastra 673xi SIP system
telephone, the Voice Activity Detection option should be deactivated for all codecs.

Media Gateway (MGW)

The Media Gateway transforms VoIP voice data into PCM audio data. This function
converts voice data between VoIP telephones and all other terminal types. Without
the Media Gateway, VoIP telephones can only exchange call data directly with other
VoIP telephones. Media Gateway functionality is also required for producing dial
tones and making external phone calls with a VoIP telephone.
A Media gateway card makes 8 channels available. One Media gateway channel
should be available for a maximum of 3 VoIP terminals. The Media Gateway also takes
over the routing function for external SIP connections, making 8 external SIP connec-
tions possible.

Software MGW

The system software of the OpenCom 100 provides one limited Media Gateway
function. Depending on system process utilisation and available system memory, up
to four MGW channels are available. The software MGW function will be automatically
activated when no Media Gateway card is present.
Using the OpenCom 131 no Media Gateway cards can be used. Here only the software
MGW function can be used for VoIP.
The Media Gateway function implemented in system software has the following limi-
tations:
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