AudioCodes Media Pack MP-124, User Manual

Page: 153 / 584

Version 6.6 153 MP-11x & MP-124
User's Manual 13. Media
4. Configure the following optional parameters:
a. Coders table - ( Configuration tab > VoIP menu > Coders and Profiles >
Coders ).
b. 'Dynamic Jitter Buffer Optimization Factor' (DJBufOptFactor) - RTP/RTCP
Settings page (
Configuration tab > VoIP menu > Media > RTP/RTCP Settings ).
c. 'Silence Suppression' (EnableSilenceCompression) - Voice Settings page
(
Configuration tab > VoIP menu > Media > Voice Settings ).
d. 'Echo Canceller' (EnableEchoCanceller) - Voice Settings page.
Note: This mode can be used for fax, but is not recommended for modem
transmission. Instead, use the Bypass (see 'Fax/Modem Bypass Mode' on
page
149 ) or Transparent with Events modes (see 'Fax / Modem Transparent
with Events Mode' on page 152 ) for modem.
13.2.1.8 RFC 2833 ANS Report upon Fax/Modem Detection
The device (terminator gateway) sends RFC 2833 ANS/ANSam events upon detection of
fax and/or modem answer tones (i.e., CED tone). This causes the originator to switch to
fax/modem. This parameter is applicable only when the fax or modem transport type is set
to bypass, Transparent-with-Events, V.152 VBD, or G.711 transport. When the device is
located on the originator side, it ignores these RFC 2833 events

To configure RFC 2833 ANS Report upon fax/modem detection:
1. In the SIP General Parameters page ( Configuration tab > VoIP menu > SIP
Definitions > General Parameters ), set the 'Fax Signaling Method' parameter to No
Fax or Fax Fallback (IsFaxUsed = 0 or 3).
2. In the Fax/Modem/CID Settings page, do the following:
a. Set the 'Fax Transport Mode' parameter to Bypass (FaxTransportMode = 2).
b. Set the 'V.xx Modem Transport Type' parameters to Enable Bypass
(VxxModemTransportType = 2).
3. Set the ini file parameter, FaxModemNTEMode to 1 (enables this feature).
13.2.2 V.34 Fax Support
V.34 fax machines can transmit data over IP to the remote side using various methods.
The device supports the following modes for transporting V.34 fax data over IP:

Bypass mechanism for V.34 fax transmission (see 'Bypass Mechanism for V.34 Fax
Transmission' on page
153 )

T38 Version 0 relay mode, i.e., fallback to T.38 (see 'Relay Mode for T.30 and V.34
Faxes' on page
154 )
Note: The CNG detector is disabled in all the subsequent examples. To disable the
CNG detector, set the 'CNG Detector Mode' parameter (CNGDetectorMode)
to
Disable .
13.2.2.1 Bypass Mechanism for V.34 Fax Transmission
In this proprietary scenario, the device uses bypass (or NSE) mode to transmit V.34 faxes,
enabling the full utilization of its speed.