Re: Phone Problems and Question

Eli Tomlinson wrote in news:telecom25.10.2@telecom- digest.org:

I have been suffering for quite some time with a PRI problem. The > short version is: > I never lose the signal, but sporadically I lose the line because of > 'bad data' or 'garbage' on the line. This can happen once a day or > thirty times a day. I am using Verizon as my PRI provider and a > Nortel BCM 400 as the phone equipment. > Verizon's position is that there is nothing wrong. Nortel's position > is that I am occassionally getting bad layer 2 data that their system > can't handle. > Both companies claim they do not have the resources or expertise to > help me ... > Do you know of anyone in the Pennsylvania, New Jersey, New York area > that is an independent telco engineer that can come in with a protocol > analyzer and give me definitive evidence of what my problem is? I > need someone with the ability to authoritatively prove my issue so I > can end the finger-pointing. > Any help or references would be greatly appreciated. > - Eli > Eli Tomlinson > Wayne Bank > 717 Main Street > Honesdale, PA 18431 > (570) 253-8566 > [TELECOM Digest Editor's Note: Maybe you should advise both companies > that you 'do not have the resources to pay for their non-help. PAT]

Eli,

If you are using an external CSU with your PBX, although the majority of PBX's incorporate a CSU function in their DS1 line cards, examine the CSU's or PBX DS1 port performance messaging (PM) registers to identify if you are experiencing any layer one line & path defects. Unfortunately the ISDN-PRI standard does not support ANSI T1-403 PM protocl with respects to Far End (FE) PM reporting from the LEC switch. Even though the local CSU & PBX port may support such an item.

A second item that you should consider exploring is the ISDN protocol used by your PBX, and the LEC (Verizon). The ISDN-PRI D channel protocol should have been negotated at the time the circuit was ordered. However my experience has shown that most sales representative, as well as CPE vendors, pay little attention to this one very important item.

Both 5ESS, and NORTEL DMS100 support ISDN National 1 & 2 protocol, as well as other vendor specific (Lucent 5E Custom is one, as well as NORTEL having their own flavors of the Q931 protocol). PBX equipment should support most common Q931 layer 3 protocols, however the beiggest headache is the naming conventions used by vendors.

To resolve an ongoing chronic ISDN-PRI trouble that exists at the ISDN D channel Q931 protocol layer, I suggest that you contact the manager of the Verizon test center that has responsibility for your account. Indicate the type of trouble you are encountering, and the relative frequency of these troubles. Just remember that if you had a trouble that cleared and was not reported to Verizon the event will not show up in the Verizon trouble history database known as WFA (Work Force Adminstration) or VZ Repair.

Request that your chronic trouble condition is referred to Verizon's Tier Two Transport Techical Support (TTS) for follow up investigation. Hopefully your ISDN-PRI T1 can be accessed remotely so that a TTS Specialist can attach an ISDN protocl analyzer to examine your ISDN circuit's D channel Q931 messages.

The Verizon TTS group operates full time, and is a more reliable group that what you will find when dealing with the normal Tier 1 maintennace center groups at Verizon. You will certainly not be charged for this service by Verizon. Especially if it is their trouble, and if it's not their trouble, Verizon TTS does not have any mechanism in place to bill customers for their time. The most thatyou would be changed with is a CPE Maintenance of Service Chanrge (MSC) for the time that was spent at your location by a service technician.

Regards,

Bill