Also sprach Jim Johnson
Thanks. I guess I should request that a telco tech go out with a T-BERD and check the lines for us to resolve this.
I am curious though, if there were a piece of equipment set for AMI coding in the circuit, wouldn't that inject either a near constant amount of errors and wouldn't it be a very large number of these Path Code Violations within a 15 min period? I am seeing 15 minute intervals with no errors, some with 2 or 3 and then a few with 60 or 70 errors within the interval.
No. Keep in mind that AMI and B8ZS serve to maintain 1's density on the circuit. If the data that's flowing over the circuit would maintain 1's density without any of the line coding "tricks" that AMI and B8ZS uses, then those mechanisms don't get triggered, the data is basically sent over raw, and no line code violations would be seens. The only time that you would see line code violations would be when there would be a timeslot on the T1 that is all 0's, then one of the mechanisms (either basic AMI, or B8ZS) would kick in, and possibly mangle one or the other as they conflict. There is an idle pattern that T1's use on channels that aren't in use (I don't know the pattern off the top of my head, but I do know that its not all 0's), so if the circuit is completely idle, it shouldn't trigger line code problems. u-law voice encoding, and v.90 pcm encoding don't ever generate all 0's either (if I remember correctly), so the only time you should ever see all 0's is when you're dealing with ISDN data calls (and then it may only be when they are running at 64kbps). Now then...I'm definitely *not* a telco engineer, so take everything I'm saying here with a grain of salt...I'm sure inaccuracies could be found. :) -- Jeff McAdams Email: jeffm@iglou.com Head Network Administrator Voice: (502) 966-3848 IgLou Internet Services (800) 436-4456 - To unsubscribe to usr-tc, send an email to "majordomo@xmission.com" with "unsubscribe usr-tc" in the body of the message. For information on digests or retrieving files and old messages send "help" to the same address. Do not use quotes in your message.