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LAPB-TA (X.75) incoming calls not managed correctly


I'm in a trouble.

I've just configured a Cisco 3600 to accept LAPB-TA incoming calls.

My customer is calling, but the 3600 doesn't accept the incoming call.

Here below I copy some row of the debug output:

=== debug output ===

*Mar 1 23:57:42.126: ISDN Se1/0:15: Incoming call id = 0x4, dsl 0

*Mar 1 23:57:42.126: ISDN Se1/0:15: received CALL_INCOMING call_id 0x4

*Mar 1 23:57:42.126: ISDN Se1/0:15: CALL_INCOMING: call type is DATA, bchan = 13

*Mar 1 23:57:42.126: ISDN Se1/0:15: Event: Received a DATA call from 471661782 on B14 at 64 Kb/s

*Mar 1 23:57:42.130: ISDN Se1/0:15: isdn_send_connect(): msg 74, call id 0x4, ces 0 bchan 13, call type DATA

*Mar 1 23:57:42.170 UTC: %LINK-3-UPDOWN: Interface Serial1/0:13, changed state to up

*Mar 1 23:57:42.202: ISDN Se1/0:15: received CALL_PROGRESSing call_id 0x4

*Mar 1 23:57:44.446: LAPB-TA: Autodetect trying to detect LAPB on Se1/0:13

*Mar 1 23:57:44.446: sampled pkt: 34 bytes: 52 49 43 48 49 45 53 54 41 20 43 4F 4E 4E 45 53.. no match

=== debug end ===

I think the problem is in the last line: "no match".

Please, has anyone encountered the same problem?

Thank in advance



Re: LAPB-TA (X.75) incoming calls not managed correctly

I have not come across this situation. But, I just happened to see this one which seems to have a good deal of information about the topic that you want. Check out if it helps you.

Community Member

Re: LAPB-TA (X.75) incoming calls not managed correctly


I haven't access to the document.

Please, could you send it to me?

Thanks in advance


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