silence on call from cisco phone to forwarded alcatel to alcatel phone

MaxBudyonny · ‎08-10-2004

We have Cisco 3745 (VOIP gateway) connected via ISDN PRI with QSIG signalling to Alcatel 4400 PBX.

All works fine. But when I am calling from Cisco IP phone to Alcatel phone which is forwarded to another Alcatel phone I hear silence and after timeout call ends.

Here is debug output of this call (debug isdn q931).

I do not see RX <- ALERTING in this output.

Aug 10 08:42:21.143: ISDN Se0/0:15 Q931: TX -> SETUP pd = 8 callref = 0x03BE

Bearer Capability i = 0x8090A3

Standard = CCITT

Transer Capability = Speech

Transfer Mode = Circuit

Transfer Rate = 64 kbit/s

Channel ID i = 0xA98381

Exclusive, Channel 1

Calling Party Number i = 0x4181, '5709'

Plan:ISDN, Type:Subscriber(local)

Called Party Number i = 0xC1, '3252'

Plan:ISDN, Type:Subscriber(local)

Aug 10 08:42:21.179: ISDN Se0/0:15 Q931: RX <- CALL_PROC pd = 8 callref = 0x83BE

Channel ID i = 0xA98381

Exclusive, Channel 1

Aug 10 08:42:21.191: ISDN Se0/0:15 Q931: RX <- FACILITY pd = 8 callref = 0x83BE

Facility i = 0x91AA06800100820100A14E02022EF306042B0C091330420A01013006800433313735020101400604038090A395A108A006800433323532820102A40BA0098004353730390A0100A5028400A70C040A4D494841494C59555441

Aug 10 08:42:41.164: ISDN Se0/0:15 Q931: RX <- DISCONNECT pd = 8 callref = 0x83BE

Cause i = 0x809080 - Normal call clearing

Aug 10 08:42:41.172: ISDN Se0/0:15 Q931: TX -> RELEASE pd = 8 callref = 0x03BE

Aug 10 08:42:41.268: ISDN Se0/0:15 Q931: RX <- RELEASE_COMP pd = 8 callref = 0x83BE

Cause i = 0x809080 - Normal call clearing

rwawrig · ‎08-10-2004

Is the switch type set to "isdn switch-type primary-net5" in cisco ?

One side has to be Network and one side has to be User. Usually, the Alcatel PBX is the network. It is like this? If no, the command "isdn protocol-emulate network" should make the cisco the master. Also the master provides the clock. Is the clock given or taken by cisco ?

MaxBudyonny · ‎08-10-2004

No I have isdn switch-type primary-qsig (in global config an on an interface), because I need qsig signalization.

If Network/User side is missconfigured ISDN layer3 would be down. In my case all works fine except when I make call from Cisco phone to Alcatel phone which is forwarded to another Alcatel phone.

Clocking is provided by Alcatel, because it is higer level in ierarchy then my gateway.

rwawrig · ‎08-11-2004

From the isdn msg it seems that cisco is receiving the CALL_PROCeeding message from alcatel, and the facility msg what include "3157" number and the name "mihai lyuta" (perhaps the destination phone after forwarding). The idea is that when the phone gets the SETUP msg from alcatel, is ringing and sends an ALERTING message back to the switch (alcatel). The ALERTING msg is sent then to cisco. This ALERTING msg is never coming to cisco, instead a DISCONNECT msg is received from the switch. Make an q931 debug on alcatel and have a look what messages alcatel is getting.

cheers

MaxBudyonny · ‎08-13-2004

I understand it. I've noticed a strange thing. If MGCP is used as a gataway control protocol I can hear alerting on Cisco phone when call is placed from Cisco phone to forwarded Alcatel phone, but Q931 debugs are the same to previous (H323 as a control protocol) and Alcatel phone does not ring.

Yet another question. How did You decode Facility string?

Thanks.

rwawrig · ‎08-13-2004

Try to use the Cisco IOS global configuration command "voice rtp send-recv" .

Also configure

"progress_ind alert enable 8"

"progress_ind setup enable 3"

in the dial-peer pots used for the call.

And make a dial peer like:

dial-peer voice xxx voip

incoming called-number .T

progress_ind setup enable 3

I'm not sure if this will force a ring tone. The commands are used to overrides PI value received in ISDN alert message when the originating gateway does not understand the H.225 Progress message.

The facility string i decode it with a q931 decoder :)

cheers

w-lam · ‎08-15-2004

check the following link:

http://www.cisco.com/univercd/cc/td/doc/product/voice/c_access/cat6000/pbx_int/217702.pdf

The problem is due to callmanager does not support the Facility IE for CallRerouting from QSIG:

"Calls did not complete when the IP phone calls an Alcatel phone that is setup to forward to another Alcatel phone. Alcatel in this case sends

Facility IE for ¡¥CallRerouting¡¦. Since Cisco CallManager 3.3 release does not support ¡¥CallRerouting¡¦, the call is not completed."