AudioCodes Mediant 3000, User Manual

Page: 743 / 872

Version 6.6 743 Mediant 3000
User's Manual 53. Configuration Parameters Reference
Parameter Description
EMS: Basic Packet Interval
[FaxModemBypassBasicRTP
PacketInterval]
Defines the basic frame size used during fax/modem bypass
sessions.

[0] = (Default) Determined internally

[1] = 5 msec (not recommended)

[2] = 10 msec

[3] = 20 msec
Note: When set to 5 msec (1), the maximum number of
simultaneous channels supported is 120.
EMS: Dynamic Jitter Buffer
Minimal Delay (dB)
[FaxModemBypasDJBufMin
Delay]
Defines the Jitter Buffer delay (in milliseconds) during fax and
modem bypass session.
The range is 0 to 150 msec. The default is 40.
EMS: Enable Inband Network
Detection
[EnableFaxModemInbandNet
workDetection]
Enables in-band network detection related to fax/modem.

[0] = (Default) Disable.

[1] = Enable. When this parameter is enabled on Bypass and
transparent with events mode (VxxTransportType is set to 2 or
3), a detection of an Answer Tone from the network triggers a
switch to bypass mode in addition to the local Fax/Modem tone
detections. However, only a high bit-rate coder voice session
effectively detects the Answer Tone sent by a remote endpoint.
This can be useful when, for example, the payload of voice and
bypass is the same, allowing the originator to switch to bypass
mode as well.
EMS: NSE Mode
[NSEMode]
Enables Cisco compatible fax and modem bypass mode.

[0] = (Default) NSE disabled

[1] = NSE enabled
In NSE bypass mode, the device starts using G.711 A-Law
(default) or G.711
µ
-Law according to the
FaxModemBypassCoderType parameter. The payload type used
with these G.711 coders is a standard one (8 for G.711 A-Law and
0 for G.711
µ
-Law). The parameters defining payload type for the
'old' Bypass mode FaxBypassPayloadType and
ModemBypassPayloadType are not used with NSE Bypass. The
bypass packet interval is selected according to the
FaxModemBypassBasicRtpPacketInterval parameter.
Notes:

This feature can be used only if the VxxModemTransportType
parameter is set to 2 (Bypass).

If NSE mode is enabled, the SDP contains the following line:
'a=rtpmap:100 X-NSE/8000'.

To use this feature:

The Cisco gateway must include the following definition:
'modem passthrough nse payload-type 100 codec
g711alaw'.

Set the Modem transport type to Bypass mode
(VxxModemTransportType is set to 2) for all modems.

Configure the gateway parameter NSEPayloadType = 100.

This parameter can also be configured in an IP Profile.