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COMfortel 1400 IP/2600 IP/3600 IP - Firmware V2.6 - Operation/Configuration - V05 09/2016
Settings
Providers and PBXs
At DTMF signalling, a sound of two overlapped sound frequencies is
assigned to each digit of the keypad. Here, you must select how the DTMF
signalling is to be transmitted. This is critically depened on the provider and
the transmission path.
Note:
If your are unsure which DMFT signalling type you must select,
you cand find out the right type by trying them out.
Outband, with local response in acc. with RFC2833
: The telephone
uses different channels to transfer DTMF signals and voice data. The DTMF
signals are filtered out of the voice data. You hear a confirmation tone to
confirm that the DTMF signals have been sent successfully.
Inband, DTMF signals sent through the audio channel
: The
telephone uses the same channel (DTMF tones) to transfer DTMF signals
and voice data.
Outband, in acc. with RFC2833
: The telephone uses different channels
to transfer DTMF signals and voice data. The DTMF signals are filtered out
of the voice data.
Codecs
A codec is a method that encodes (digitises) analogue voice data for trans-
mission and again decodes again, meaning converts into back into voice.
There are various codecs that feature different voice data compression
rates thereby require different band widths for data transmission. The
equality of VoIP calls is dependent on the codec used.