406 w/ T1: Any T1 signaling gurus out there? loop start

[icmpman]

Fellow techs & engineers:
I have a T1 configured as loop start (b/c that's what the provider feeds the IP office from adtran 600R). When far-end caller hangs up, ip office end gets dial tone instead of hanging up. This problem also shows up when someone leaves a voice-mail message and records 2 minutes of dial tone at the end of every message.

Here is trace of the hangup:
136807mS PRN: T1 CAS: Channel LS 5.1: RX: 0101 -> 1111
136807mS PRN: T1 Channel: LS 5.1: EventRx Ringing state=Talk
137792mS PRN: T1 CAS: Channel LS 5.1: RX: 1111 -> 0101
137792mS PRN: T1 Channel: LS 5.1: EventRx Not Ringing state=Talk

It goes from off-hook to network disconnect on line 136807. The IP office end just gets dial tone forever and never hangs up. It doesn't matter whether ip office initiated call or not. Any ideas, guidance, resources, configuration options to consider?

 

[SuperJenks]

First of all, what type of t-1 is it? It sounds like a supervision problem. If it is a standard t-1 with E&M signaling, your probably not seeing the wink correctly from the provider. If that is the case the system will get confused on when to stop or start the call. If the circuit is a PRI, its hard to say without seeing whats happening first hand.

 

[icmpman]

SuperJenks, you are correct, apparently. (BTW, line sub type is just t-1). I was originally told that the service provider's equipment would only do loop start. I had them come back to try to work through the details.

Resolution: Once his equipment and the IP Office were configured for ground-start (instead of loop start), all disconnect issues were cleared up.

Now just have to figure out why caller-id won't work!! I'm starting a new thread on that one.