H3C Technologies H3C MSR 50 - Manual (Page 594)

209
Item Description
ECM Fax
As defined in ITU-T, the ECM is required for a half duplex and fax message transmission
using the half-duplex and half-modulation system of ITU-T V.34 protocol. Besides, the G3
fax terminals working in full duplex mode are required to support half-duplex mode, that is,
ECM.
The fax machines using ECM can correct errors, provide the automatic repeat request
(ARQ) function, and transmit fax packets in the format of HDLC frames. On the contrary,
the fax machines using non-ECM cannot correct errors and they transmit fax packets in the
format of binary strings.
• Enable—Enable ECM for fax.
• Disable—Disable ECM for fax.
By default, ECM is disabled.
ECM can be adopted only if fax machines on both sides support ECM and the gateways
are configured with ECM.
You must enable ECM mode for the local numbers and call routes corresponding to the fax
sender and receiver in the ECM mode.
CNG Fax
Switchover
Function
Implements the CNG fax switchover is mainly used to implement the fax mailbox service
through communication with the VCX. When the local fax machine A originates a fax call
to the peer fax machine B, if B is busy or is unattended, A can send the originated fax to
the fax mailbox of the VCX. With CNG fax switchover enabled, the voice gateway can
switch to the fax mode once it receives a CNG from A.
• Enable.
• Disable.
The function is disabled by default.
Codec Type and
Switching Mode
for Modem
Pass-through
Configure the codec type and switching mode for modem pass-through function.
• Standard G.711 A-law—Adopt G.711 A-law as the codec type and use Re-Invite
switching for modem pass-through.
• Standard G.711 μ-law—Adopt G.711 μ-law as the codec type and use Re-Invite
switching for modem pass-through.
• NTE Compatible G.711 A-law—Adopt G.711 A-law as the codec type and use
NTE-compatible switching for modem pass-through.
• NTE Compatible G.711 μ-law—Adopt G.711 μ-law as the codec type and use
NTE-compatible switching for modem pass-through.
NTE Payload
Type Field
Configure the value of NTE payload type for the NTE-compatible switching mode.
This option is configurable only when NTE Compatible G.711 A-law or NTE Compatible
G.711 μ-law is selected from the Codec Type and Switching Mode for SIP Modem
Pass-through list.
By default, the value of the NTE payload type is 100.
Configuring fax and modem parameters of a call route
Select Voice Management > Call Route from the navigation tree, and then click the icon of the call
route to be configured to access the call route fax and modem configuration page.