AudioCodes Mediant 1000B - Fax;Modem Operating Modes; Fax;Modem Transport Modes

Version 7.2 189 Mediant 1000B Gateway & E-SBC
User's Manual 14. Media
 To access the fax and modem parameters:
1. Open the Fax/Modem/CID Settings page (Setup menu > Signaling & Media tab >
Media folder > Fax/Modem/CID Settings).
Figure 14-3: Fax/Modem/CID Settings Page
2. Configure the parameters, as required.
3. Click Apply.
14.2.1 Fax/Modem Operating Modes
The device supports two modes of operation:

Fax/modem negotiation that is not performed during the establishment of the call.

Voice-band data (VBD) mode for V.152 implementation (see ''V.152 Support'' on page
198): fax/modem capabilities are negotiated between the device and the remote
endpoint at the establishment of the call. During a call, when a fax/modem signal is
detected, transition from voice to VBD (or T.38) is automatically performed and no
additional SIP signaling is required. If negotiation fails (i.e., no match is achieved for
any of the transport capabilities), fallback to existing logic occurs (according to the
parameter IsFaxUsed).
14.2.2 Fax/Modem Transport Modes
The device supports the following transport modes for fax per modem type
(V.22/V.23/Bell/V.32/V.34):

T.38 fax relay (see ''T.38 Fax Relay Mode'' on page 190)

G.711 Transport: switching to G.711 when fax/modem is detected (see ''G.711 Fax /
Modem Transport Mode'' on page
192)

Fax fallback to G.711 if T.38 is not supported (see ''Fax Fallback'' on page 193)

Fax and modem bypass: a proprietary method that uses a high bit rate coder (see
''Fax/Modem Bypass Mode'' on page
193)

NSE Cisco’s Pass-through bypass mode for fax and modem (see ''Fax / Modem NSE
Mode'' on page
195)

Transparent with events: passing the fax / modem signal in the current voice coder