Help with ISDN connection

[signalgrunt]

I've been rackin my brain all morning. I have a tandberg 2500 connected with ISDN. When I started the system up this morning, one of the lines wouldn't come up. I can connect at 256 but not 384. I'm using an Adtran 512 ISDN modem with 3 ISDN lines coming into the back. Nothing has changed on the system since yesterday and I even went in to the configuration menu on the Adtran to check several times. I'm not all that familiar with this stuff so if anyone thinks they may know what the problem is I am open to suggestions.

[pbraatelien]

Signalgrunt,
Does the adtran still give the correct lighting (green, not flashing) and does it show the lines up?
Very rarely is it the equipment--mostly network, but here are a few things you can try.
1. Unpug the bad ISDN line from the wall (or if you do not know which one-then do all of them. Wait a minute and the plug them back in.
2. If you know which one it is try changing it with another one (you would have to reprogram the lines in the Tandberg) this should point to a network or system problem
Paul

[signalgrunt]

When I unplug and re plug in a line in a different socket I have to reprogram the SPID numbers and LDNs for that line in the Adtran. I do all dialing from the Adtran. The Tandberg is only connected via the RS530 cable to send the signal to the Tandberg once the Adtran has connected.

I tried what you said. The bad line is the 3rd one. I even tried taking the cable from line 2 and plugging it into line 3 both at the wall and the Adtran and that line is still down so it looks like it's definitely not the cable.

Help!

[pbraatelien]

Well,
Its gotta be the network then. How is it provided to you? Is it thru the PBX or a carrier? YOu may have to call them to get them so fix it/activate it, or run tests. Also have you tried to have someone dial into it?
Paul
pm me with your phone number is you like and I may be able to talk you thru it.

[George]

I'd have to agree with pbraatelien.

If you are 100% positive that that 3rd BRI is configured properly in the Adtran then it's a problem outside of your room. SO if you look at it from a reverse troubleshooting aspect, what's your next Point Of Failure?

My guess is it's the local switch where those BRIs are terminated. Just start making phone calls from POF to POF until you nail it down. Call the switch tech and ask them to look at your circuit both on the PRI side and internally. They can tell you if the problem is past the switch. If it's not then they may simply have to reset the BRI card on the switch and then you can get on with life.

Let us know if you need more help!

[signalgrunt]

Just came back to let you know that your resolutions helped me to fix the problem. It was at the switch afterall. Thanks to pb because I would have never even started pulling cables or even thinking in that direction. I was convinced that it was the Adtran. George you were right on. The guy at the CO where my switch is told me my card was in alarm and after he reset it and I reset my Adtran it came right up.

[dndtech]

A little further info for those with similiar problems in the future. If you turn off your local connection device (Adtran, NT1 etc.) your service providing equipment, (PBX, DMS, etc.) may disable itself. Some certainproviding hardware may be set to self disable if it can't see a termination device during a poll. You may have to contact your service provider to re-enable the circuit. Several reasons have been given to me for this setting like protecting against unathourized usage of your bandwidth.
The fault finding procedure in the previous threads are bang on. The local hardware rarely fails, but should be checked before calling your carrier. Cheers.

[George]

Hey that's a good point dndtech. I have experienced this same problem in the past myself and was wondering whether either a) my local switch techs are morons and don't know how to configure the switch properly because it keeps doing that or B) there is a hardware problem with the switch.

This clears things up a bit and I am going to pass this on to them. Thanks.

[tjulian]

Also of note, the Adtran ISU 512 IMUX very, and I do mean VERY, rarely fails.

Another thing that may help to reset/resync your ISDN lines is to power down your IMUX/system, and leave it off for 30 seconds to a minute. Some older switches seem to get lost when the power is turned off and right back on, and this allows the circuits time to reset. It doesn't always work, but sometimes it does.

Oh yeah, and never listen to the Telco when they tell you its your equipment. I've had my equipment miraculously "fix" itself overnight on several occasions, in different locations, and the Telcos all still claim that they never had a problem...yah, right!

[jbad67]

I have a difficult problem, my VTC can make unsecure calls with no problem but when i go secure the far end VTC hub is taking hits and causing the call to freeze and drop. I had the teleco check the lines and everything is fine. It is just the secure VTC call that is my problem, it has been working in the past fine but just started this. Could it be a timing issue somewhere or what. Out of ideas!!!! john

[vtjoe]

I have a difficult problem, my VTC can make unsecure calls with no problem but when i go secure the far end VTC hub is taking hits and causing the call to freeze and drop. I had the teleco check the lines and everything is fine. It is just the secure VTC call that is my problem, it has been working in the past fine but just started this. Could it be a timing issue somewhere or what. Out of ideas!!!! john


You left out a lot of information - What network - ISDN or IP?

For Securing the call - are you using an external box or internal?
(If external box you might want to start a thread under"Secure Conferencing")

Assuming you are using ISDN, are you using the same ISDN lines for secure and non-secure calls?

What endpoints are you using - Tandberg, Polycom, PictureTel?

[jbad67]

We are using the same ISDN lines for making secure and unsecure calls. We are using a KIV-7 for securing the calls. Also we have tandberg equipment that is connected to crypto that connects to a adtran. We are connecting to the far end thru a secure bridge (mcu).
Hope this helps.

[haneyr]

Have you tried getting a loopback from a distant end to see if the problem is on your side or the other site. What is your KIV-7 doing? Is it losing sync?

[jbad67]

yes we have tried a loopback from a distant end and we are getting errors causing the kiv to lose sync. Also noticed that the call will drop but somehow the equipement is still seeing the call and causing our isdn cards to burn up.

[haneyr]

Sounds like a cable pinout or kiv config problem. Check the other strings and see if you are properly configured.