ISDN video conference 1 of 3 lines not working 1

[Imstillhere]

Hello and thank you for taking the time to review my question. I didnt know zip about this a couple days ago,but we have a Video conference room downstairs they said the quality of the video was bad.. well the equiptment attached to it shows line 1 with a fast blink the other 2 say ready. I found that the fast blink means the circuit is down.. call telco.. Well of course they say its fine and I need to turn it up? I know DID circuits used to have to be turned up but.... anyway i got the spid numbers from the telo after tracing the lines to the Dmarc to read the circuit #'s and dialed them adding 0101 (what telco said to do)and each returns a dial tone.What purpose did that serve if the line is still down? How do I do a basic TROUBLESHOOT on these lines without a $1500 isdn tester ? I did move the lines around on the equip but the problem always followed line 1?

 

[ISDNman]

Yes. Confirm it the good lines work in all three jacks and the bad line work in non-of the three jacks.

Then plug them back into the unit and call the Telco and ask them to do "a loopback through the NT1 for at least 15 minutes". If the "can't see the NT1" tell them the same NT1 works fine on another line and they need to fix this one.

If they say "we see errors" tell then we know the errors are on the line because the same NT1 works just fine on 2 other lines.

Best of luck. Don't give up and don't let them close the ticket till it is working.

If you ask a better question you will get a better reply. Be specific so we can help!

 

[Imstillhere]

I requested them come out and show me it was good at the DMARC, of course they could not,they found a problem in the CO. So im up and running and thank you for the loop back tip on the NT1.I will know next time what to ask for.. P.s. Is the some sort of local loopback test in NT1 devices OR can you make a loopback type plug for these lines like you do a T1 ?

 

[ISDNman]

Good job.

No, unfortunately there is no loopback on the user side of the NT1.

You can of course dial B1 to B2 and before a dual channel loopback that way (BERT's both channel at once). With audio codecs you can get your own audio back this way.

But if the line is down you can't dial.... etc.

If you ask a better question you will get a better reply. Be specific so we can help!

 

[Imstillhere]

If you dont mind, I would also like to know why did line 1 have only one spid# accociated with it, while lines 2 & 3 each had two spid #'s associated . And what do I accomplish when calling them and adding the 0101 after the spid? (each number gave me dialtone after entering 0101) even when line 1 was down ?
If its a dont worry aboit question then just let me know and I wont worry about it
Thanks again !!!!

 

[ISDNman]

SPID = Service Profile ID. Originally ISDN was intended to allow multiple devices to share the same ISDN line by connecting together on the user side of the NT1 (S interface). Once the NT1 is built in (U interface, for direct connection to the line)this is generally not possible.

Anyway, since there are so many potential features it was thought that not all devices would support all features. So the system was designed that multiple service profiles could exist on a line, with each service profile having only a specific group of features. Each device would get only the correct features by giving the service profile ID that was appropriate for it.

All of this is ancient history. From a practical matter most lines have 2 SPIDs both of which access the same features (e.g the same service profile) . It is important to understand the fact that the SPID is not a phone number and could in fact be a random number assigned by the Telco. You would still need to enter that(these) number(s) to get the terminal device to work.

*Usually* there are two SPIDs each associated with a separate phone number (e.g. 2 SPIDs and 2 Phone numbers [also called directory numbers].

There are other possibilities such as one SPID and 2 telephone numbers. Or one SPID and one Telephone number. In this last case the line will (usually) respond to 2 calls to that number, like a hunt group between the two channels of the BRI.

When calling a line only the phone number is used. I didn't understand what you meant about getting dial tone the first time, nor in your latest post, so I can't really answer that question. When calling from a telephone into a data device such as a codec I would expect you to get busy or fast busy. Or *Maybe* ring back tone. I certainly would not expect dial tone.

I hope this helps versus confusing you more

If you ask a better question you will get a better reply. Be specific so we can help!

 

[Imstillhere]

Yes, when i go off hook dial 9 then spid. I get dial tone and the guy at telco said to the enter 0101 to tun it on,I was just suprised i got a dial tone when calling the SPID of the circuit that was having the problem.I would have assumed it would give me some indication the circuit was in trouble.... anyway...no big deal.
I appreciate the 101 on ISDN. Thank you again and
HAVE A GOOD WEEEKEND !!