atcomsystems.ca/forum Forums Wiring - Telecom Carriers - Trunks & Services T1's, CSU's and DSU's PRI problem; I am running out of options

I've never heard of this type of symptom with PRIs. Good job isolating this problem down to impacting only the CID associated calls. I like your point Bill, but I wouldn't rule out a local software problem; possibly a corrupted file, that's misinterpreting the CID datastream and disconnecting the call (I wish we could test an inbound call at the demarc with a TPI 570): Ed, in your original post, you mention that when your client was using XO Communications, the PRI "went down" as many as 3 times a day.."Went Down" = Inbound calls dropping after 1st ring also?

I'm assuming it's the same as a POTS as to where it's inserted and it also fits in with Ed's trouble shooting. I don't know it for a fact Larry. Guess I should has worded it as an assumption on my part. I would also assume the CID is sent over the talk path and not the D channel. I don't know near as much about ISDN service as most of you though.

Just Bill

Just for info the PRI CID info is sent over the D channel as you stated along with the did digits. The switch and the telephone system negotiate in a way the channel that the call is going to be on and then the call is connected.

As for the cause of calls not completing when CID info is sent. I know I have had this problem before but I do not remember what it was. I will call one of my switch buddies and see if he remebers.

He ed.

Do you have an option to set your dialing plan to unknown.

Yep, I shouldn't have even commented on it. Thanks for the information.

Ed, I don't know this system but on the older Toshibia DK's this would happen if the name was sent with the caller id info.

We had a similar problem only reversed could receive can't call out. 3 days later a very tired and irate Embarq tech (10:00 @ night)who could not call out on his T Berd chewed out his own CO programmers and we all found out the problem together. Software upgrade Nortel had done recently on fairly new Central Office was the problem, they had to move the circuit back to some of the old equipment to get it to work. Not sure what they did with the circuit after that but it hasn't missed a beat since. Good luck Ed I feel your pain!

POTS: I really don't know if name is being sent, but that's a great thing for us to check. Their former PRI account didn't have name. I am still confused as to why name would have been added to a 40-day old account without being requested, but we ARE dealing with Verizon.

BReed: I am sure that what you experienced is causing the same thing here. Seems as if DMS offices are not as resilient as ESS's when maintenance or upgrades are performed.

ALLN1: Yes, we have the option of "unknown", but that only applies to outward dialing. Outward dialing works fine.

JustBill: I am in agreement with you about the CID info being sent between ring cycles ONLY because a virtual POTS line came into the equation recently as their failsafe rerouting destination. It seems as if Verizon activated this virtual POTS line, set it up for a test, then forgot to take it off after the test. With a virtual number within the switch having no assigned destination, I would think that the call to it would be rejected. This is exactly what is happening.

All that I know is that a call with the number blocked gets through, but the minute that calling party information is sent (unblocked call), it returns one ringback tone and then drops the call. At least this problem is consistent.

Ed,

I have seen a very similar problem on an XTS MPB2, where the carrier was supplying a PRI from a DMS 10 and for some reason the Caller ID out of the blue would cause our PRI board to go out and then actually reset the whole system every time a call would come in. Worked with vodavi and we had the carrier turn off Caller ID and BAM the circuit worked fine. They rebuilt the circuit with CID and it ran fine for a while and a few weeks later the same thing had happened call would come in and mass confusion would start. The carrier ended up fixing the problem on their switch and we have not had any issues since. let me know if you need anything else or mybe if i can explain it better to you.

I meant to send a PM. Please delete this. Thanks!