ISDN BRI Issue

[richard.jackson]

I am currently testing callmanager 7 with a new service provider switch, however I am having issues with BRI interfaces.

I am unable to make a call on an ISDN BRI port under MGCP control (works fine as H323)

The debug message on Q931 is

*Mar 11 17:33:55.383: ISDN BR0/1/0 Q931: TX -> SETUP pd = 8  callref = 0x09

        Sending Complete

        Bearer Capability i = 0x8090A3

                Standard = CCITT

                Transfer Capability = Speech

                Transfer Mode = Circuit

                Transfer Rate = 64 kbit/s

        Channel ID i = 0x8A

                Exclusive, B2

        Calling Party Number i = 0x0081, '2005'

                Plan:Unknown, Type:Unknown

        Called Party Number i = 0x80, '749810'

                Plan:Unknown, Type:Unknown

*Mar 11 17:33:55.443: ISDN BR0/1/0 Q931: RX <- SETUP_ACK pd = 8  callref = 0x89

        Channel ID i = 0x8A

                Exclusive, B2

*Mar 11 17:33:55.447: ISDN BR0/1/0 Q931: TX -> STATUS pd = 8  callref = 0x09

        Cause i = 0x82E2 - Message not compatible with call state or not implemented

        Call State i = 0x01

*Mar 11 17:33:55.575: ISDN BR0/1/0 Q931: RX <- CALL_PROC pd = 8  callref = 0x89

*Mar 11 17:33:55.579: ISDN BR0/1/0 Q931: TX -> STATUS pd = 8  callref = 0x09

        Cause i = 0x82E0 - Mandatory information element missing

        Call State i = 0x01

*Mar 11 17:33:55.595: ISDN BR0/1/0 Q931: RX <- RELEASE_COMP pd = 8  callref = 0x89

        Cause i = 0x82E5 - Message not compatible with call state

*Mar 11 17:33:55.715: ISDN BR0/1/0 Q931: RX <- RELEASE_COMP pd = 8  callref = 0x89

        Cause i = 0x82E5 - Message not compatible with call state

However the Debug on the old existing Service provider is

*Mar 11 17:17:35.471: ISDN BR0/1/0 Q931: TX -> SETUP pd = 8  callref = 0x01

        Sending Complete

        Bearer Capability i = 0x8090A3

                Standard = CCITT

                Transfer Capability = Speech

                Transfer Mode = Circuit

                Transfer Rate = 64 kbit/s

        Channel ID i = 0x8A

                Exclusive, B2

        Calling Party Number i = 0x0081, '2005'

                Plan:Unknown, Type:Unknown

        Called Party Number i = 0x80, '749810'

                Plan:Unknown, Type:Unknown

*Mar 11 17:17:35.691: ISDN BR0/1/0 Q931: RX <- CALL_PROC pd = 8  callref = 0x81

        Channel ID i = 0x8A

                Exclusive, B2

*Mar 11 17:17:36.047: ISDN BR0/1/0 Q931: RX <- ALERTING pd = 8  callref = 0x81

        Progress Ind i = 0x8482 - Destination address is non-ISDN

The Only difference I can see is that the new system sends an Setup ACK message. However I am unable to ascertain what information is missing. Does anyone know if there is a setting I can change in the Service Parameters that needs to be changed????

Many thanks in advance

[paolo bevilacqua]

No information is missing, CM is misbehaving. It expects channel information to be in Call Proceeding and not in Setup Acknowledge, however per Q.931 standard, it can be in either message (that incidentally, convey slightly different semantic).

I'm unable to tell you why, and if it is fixable.

I would recommend stay with H.323, more features, more stability, easier to configure and troubleshoot.

[richard.jackson]

Thanks for the reply, unfortunately as the Telco Provider I have to carry out User Acceptance Testing for CallManager and this is a fail. As such I either need to find a fix for this or state that CallManager will not work with the Telco Switch we provide as a MGCP  option

[paolo bevilacqua · Accepted solution]

That is correct statement, your only other option beside the safe harbor of H.323  is a potentially long and fruitless interaction with the TAC.

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