FXO Problem
Ben Oct 9, 2009 7:07 PMHi
I'm having a problem making an outbound call (VoIP -> PSTN) using a VIC-2FXO card in a 1760V (running 12.4(15)T7) and was hoping someone might be able to point me in the right direction.
-The 1760V is running CUCME 4.1 (10.1.1.1/24)
-I am using a Blue Ip Softphone to initiate the call
-I can successfully answer a call from the PSTN on the VoIP device
-the PSTN line is plugged into port 0 of the VIC-2FXO card (slot 3) via an RJ-11 cable
-if I plug a normal analogue handset into the same RJ-11 cable coming into the VIC-2FXO I can make a call
-I can use DTMF from an anlogue phone to dial out (hence have set dial type to DTMF)
Here are the relevent bits of running-config:
!
voice-port 3/0
supervisory disconnect dualtone mid-call
pre-dial-delay 2
ring number 2
no echo-cancel enable
cptone AU
timeouts call-disconnect 3
timeouts ringing infinity
timeouts wait-release 3
timing min-ring 200
connection plar 1001
impedance complex1
description Connected to the PSTN
!
voice-port 3/1
impedance complex1
!
!
!
!
!
!
dial-peer voice 1 pots
destination-pattern .T
no digit-strip
port 3/0
!
Via a #debug vpm signal, I believe the line is going OFF Hook and the VIC-2FXO/CME is sending the dialled digits via DTMF, however the PSTN number never rings and the CME appears to do some bridging fullback feature where the extension ends up in an 'empty' call with the CME acting as the called endpoint (10s timeout). See attached debug trace.
I think the problem could be either:
-DTMF digit duration is wrong
-DTMF inter-digit duration is too long/short
-the line is being seized too early before it is ready to receive DTMF
All basically meaning the CO is not able to detect the destination I am trying to reach and hence why CME does its bridging feature after the 10s timeout.
The default DTMF Duration/DTMF inter-digit (100ms/100ms) did not work so I hunted around for some recommened Australian settings. I found one document which mentioned using 80ms/80ms but this did not work either. I then increased the pre-dial-delay for the FXO port from 1 to 2s but this did not help either. I noticed via a show voice port 3/0 that the companding type is set to u-law. I know in Australia we use a-law but I believe this setting is only applicable for digital signalling (ISDN/Q.931)
I have also set the interface impedance to 220+820 | 120uF (which I changed via setting to impedance complex1) and the tones to Aus specific (cptone AU)
One thing that confuses me a little is that the #show dialplan number command only matches my VoIP devcies and does not come back saying the POTS dial-peer would be used if I enter any number ( eg .T) other than the VoIP extensions .
Any comments/suggestions wold be appreciated
Regards
Ben