terminating device. This option is useful, for example, when
the originating device is located behind a firewall that blocks
incoming T.38 packets on ports that have not yet received
T.38 packets from the internal network (i.e., originating
device). To also send a Re-INVITE message upon detection
of a fax CNG tone in this mode, set the parameter
FaxCNGMode to 1.
[2] Events Only = CNG is detected on the originating side
and a fax session is started by the originating side using the
Re-INVITE message. Usually, T.38 fax session starts when
the ‘preamble’ signal is detected by the answering side.
Some SIP devices don’t support the detection of this fax
signal on the answering side and thus, in these cases it is
possible to configure the device to start the T.38 fax session
when the CNG tone is detected by the originating side.
However, this mode is not recommended.
Note: This parameter can also be configured in an IP Profile.
Web: Fax Relay Enhanced
Redundancy Depth
EMS: Enhanced Relay
Redundancy Depth
[FaxRelayEnhancedRedundancy
Depth]
Defines the number of times that control packets are
retransmitted when using the T.38 standard.
The valid range is 0 to 4. The default is 2.
Web: Fax Relay Redundancy
Depth
EMS: Relay Redundancy Depth
[FaxRelayRedundancyDepth]
Defines the number of times that each fax relay payload is
retransmitted to the network.
[0] = (Default) No redundancy
[1] = One packet redundancy
[2] = Two packet redundancy
Note: This parameter is applicable only to non-V.21 packets.
Web: Fax Relay Max Rate (bps)
EMS: Relay Max Rate
[FaxRelayMaxRate]
Defines the maximum rate (in bps) at which fax relay messages
are transmitted (outgoing calls).
[0] 2400 = 2.4 kbps
[1] 4800 = 4.8 kbps
[2] 7200 = 7.2 kbps
[3] 9600 = 9.6 kbps
[4] 12000 = 12.0 kbps
[5] 14400 = 14.4 kbps (default)
Note:
adapts to the capabilities of the remote side). Negotiation of the
T.38 maximum supported fax data rate is provided in SIP’s SDP
T38MaxBitRate parameter. The negotiated T38MaxBitRate is
the minimum rate supported between the local and remote
endpoints.
Web: Fax Relay ECM Enable
EMS: Relay ECM Enable
[FaxRelayECMEnable]
Enables Error Correction Mode (ECM) mode during fax relay.
[0] Disable
[1] Enable (default)
Web: Fax/Modem Bypass Coder
Type
EMS: Coder Type
Determines the coder used by the device when performing
fax/modem bypass. Typically, high-bit-rate coders such as
G.711 should be used.