BCM 400 static on PRI Channel

[BCM400Noob]

I'm getting vague complains of periodic static on my PRI channels.

Is there an easy way to select a B-Channel from my nortel phone and make some test outbound calls? A Feature code, perhaps?

 

[Deweyhumbolt]

No, all you can do is Deprovision.

Adversity is Opportunity

 

[SupportDude]

You can Deprovision and Disable the B channels.
This will allow you to force the call to a specific B channel.
Typically, outbound calls will use the highest available channel, like 23. If you deprovision and disable 23, calls will now go out 22.
Conversly, inbound calls are opposite, starting at the lowest available channel. So, deprovisioning and disabling B1 will force the next inbound call to use B2.
You can continue disabling channels in pairs, one low and one high, and making calls in and out in until you've been able to test all of the channels.

-SD-

http://www.mysupportguy.net

 

[BCM400Noob]

I'm pretty sure I've narrowed the problem down to an inbound channel, so probably in the first 5.

Since unless I do this during off hours, I can't be sure someone slips in on an inbound line while I'm attempting to test it. Is there a way on the phone to identify the incoming line?

Perhaps even flag it as a trouble line so I can give my users something to do?

 

[SupportDude]

Unfortunately no.
They can stamp the logs with F9*9, but you would have to download, analyze, and interpret the logs for that to be of any value.
They can try Feature 811 while on a call to see if they can determine the line in use, but it will most likely show the target line number not the PRI trunk line number.

If you know how to use BCM Monitor, the UIP tab can help you find the B channel. But, you would need to have the monitor running and they would need to call you with the call up when they experience static.

-SD-

http://www.mysupportguy.net

 

[BCM400Noob]

I just installed the BCM Monitor and that look really helpful. Not sure what the UIP tab shows but the line monitor looks like it will be very helpful. It seems to show the last User and the start time of the last call--please confirm my observation.

I have lines 61 through 83 as my B channels. From a previous post, I can see that 61-69 were last used for incoming and 74-83 for outgoing. 70-73 are not shown. I'll verify that they are provisioned, but it is possible that they have not been used since the last reboot.

I'm guessing that my issue is not with the first trunk or two and from telco reports, my peak trunk usage during a day with the most complaints was about 18%

 

[SupportDude]

Sounds about right to me.
Incoming calls from low to high, and outgoing calls from high to low. It is possible you've never had enough active calls to get up to 70-73.

The UIP tab will show you the D channel messaging.
Very helpful in certain situations.

-SD-

http://www.mysupportguy.net

 

[gberger]

I had an issue once with a PRI, on the first call the voice was perfect, as soon as someone else would make a second call at the same time, the voice would degrade and so on, after 4 calls it was completely inaudible.
It turned out to be the PEC cards, rebooting,replacing the DTM module had no effect, the problem cleared after reseating the PEC cards...

 

[clutse]

This sounds like a "hot" PRI. It may not be so "hot" as to cause static on every call. This scenario becomes a problem when a user calls a number associated with another "hot" span. Usually you can alleviate this type of problem by padding the db of the PRI.

 

[SupportDude]

I've changed out PECs before to clear static on IP sets, but not on a PRI.
Good thought clutse ... I did have an issue with a hot PRI several years back. After working with Nortel on it for several weeks, we changed the setting from ISDN to whatever the other option is and it padded the PRI to the point that the static was unnoticeable.
Might give that a shot BCM400Noob.

-SD-

http://www.mysupportguy.net

 

[ExtraPepper]

Do you have any VOIP Trunks enabled? Perhaps you can use VOIP Trunks to rule out or in the BCM hardware by determining if the static appears on calls using VOIP Trunks.

RAJ Brown