AS5850 Cisco IO12.4(7c),
The used protocol is MGCP with a call agent.
the behaviour we want for the gateway is to be able
to have fax transmission in G711 codec
without nse - without t38
The mgcp parameters are on mgcp side
MGCP Admin State ACTIVE, Oper State ACTIVE - Cause Code NONE
MGCP call-agent: 172.20.xx.xx 2727 Initial protocol service is MGCP 1.0
MGCP validate call-agent source-ipaddr DISABLED
MGCP validate domain name DISABLED
MGCP block-newcalls DISABLED
MGCP send SGCP RSIP: forced/restart/graceful/disconnected DISABLED
MGCP quarantine mode process/loop
MGCP quarantine of persistent events is ENABLED
MGCP dtmf-relay voip codec all mode out-of-band
MGCP dtmf-relay for voAAL2 is SDP controlled
MGCP voip modem passthrough disabled
MGCP voaal2 modem passthrough disabled
MGCP voip modem relay: Disabled.
MGCP T.38 Named Signalling Event (NSE) response timer: 200
MGCP Network (IP/AAL2) Continuity Test timer: 200
MGCP 'RTP stream loss' timer disabled
MGCP request timeout 3000
MGCP maximum exponential request timeout 4000
MGCP gateway port: 2427, MGCP maximum waiting delay 5
MGCP restart delay 0, MGCP vad DISABLED
MGCP rtrcac DISABLED
MGCP system resource check DISABLED
MGCP xpc-codec: DISABLED, MGCP persistent hookflash: DISABLED
MGCP persistent offhook: ENABLED, MGCP persistent onhook: DISABLED
MGCP piggyback msg DISABLED, MGCP endpoint offset DISABLED
MGCP simple-sdp ENABLED
MGCP undotted-notation ENABLED
MGCP codec type g729r8, MGCP packetization period 40
MGCP JB threshold lwm 4, MGCP JB threshold hwm 100
MGCP LAT threshold lwm 150, MGCP LAT threshold hwm 300
MGCP PL threshold lwm 1000, MGCP PL threshold hwm 10000
MGCP CL threshold lwm 1000, MGCP CL threshold hwm 10000
MGCP playout mode is adaptive 50, 30, 100 in msec
MGCP Fax Playout Buffer is 300 in msec
MGCP media (RTP) dscp: ef, MGCP signaling dscp: ef
MGCP default package: trunk-package
MGCP supported packages: gm-package dtmf-package trunk-package rtp-package
ms-package dt-package mo-package res-package mt-package
fxr-package
MGCP Digit Map matching order: shortest match
SGCP Digit Map matching order: always left-to-right
MGCP VoAAL2 ignore-lco-codec DISABLED
MGCP T.38 Max Fax Rate is 14400 bps
MGCP T.38 Fax is ENABLED
MGCP T.38 Fax ECM is ENABLED
MGCP T.38 Fax NSF Override is DISABLED
MGCP T.38 Fax Low Speed Redundancy: 0
MGCP T.38 Fax High Speed Redundancy: 0
MGCP control bound to interface Loopback2
MGCP media bound to interface Loopback1
MGCP Upspeed payload type for G711ulaw: 0, G711alaw: 8
MGCP Dynamic payload type for G.726-16K codec
MGCP Dynamic payload type for G.726-24K codec
MGCP Dynamic payload type for G.Clear codec
MGCP Dynamic payload type for NSE is 100
MGCP Dynamic payload type for NTE is 101
MGCP Guaranteed scheduler time is disabled
The T38 is enabled on the gateway but the CA doesn't ask for a T38 fax
The Fax must work in V17 (group3)
The comm is established direclty to G711
The CA send REQNT for ft d?tection
The MGW send NTFY when the ft is observed
but it send also 3 NSE packets PT=100.
Which is very surprising because we are no modem passthrough mode nse.
If we modify the mgcp configuration, there is nore more paquets NSE
but
our wish is to have only a configuration from which it must be possble to perform g711 ot t38 fax using
mgcp (without modification of the GW depending on the service type that can used it)
is there some additionnal modification on this GW possible to perform this.
