definity XE + T1 = glare problem

[1capybara]

we have a definity XE R6 with 3 hybrid cards (TN762B)
and 8 analog cards (TN746B) amd a tn747B trunk card.
We are connected by T1 provided by mpower, running through
a adtran 616 box in the bridge mode.
we have a bad glare problem.
sometimes when you pickup the phone to call out, you are connected to someone trying to call in. (the trunk line is simultanously selected on both its incoming and
outgoing ends.) is there a software or hardware solution?
our definity provider blames mpower's T1 poor line quality.
can this be the cause?
NOTE THIS: the problem is only on the hybrid cards.
a poossible solution i hope to avoid is going to all
analog cards.
has anybody had this problem and fixed it?

 

[OldPhoneGuy]

Is your co trunk group trunk type set up for loop start or ground start? Ground start trunks prevent glare. If the Adtran is providing loop start service can it be reconfigured to provide ground start trunks?

 

[lopes1211]

Or get rid of the Adtran and terminate directly to a T-1 card in the PBX. You have a poor Definity vendor for them to claim "poor T-1 quality". It's a pretty straight forward issue with the loop start FXS lines from the adtran like OPG says. I don't think you can have a ground-start FXS ports however.

-CL

 

[sezwhat]

This is definitely not a fix, but one way to minimize this is to have the Definity use the last trunk in the group as the first outbound choice and work backwards. Can't recall how the Definity makes it's selection, but it may be as simple as deleting the trunks and adding them back in reverse order. This will limit the glare to times when all trunks in the group are busy.

 

[1capybara]

im pretty sure we are ground start trunks.
unfortunately, i dont think we can terminate the T1 directly
to the pbx, an adtran is necessary because our T1 is also
used for data (internet). But changing the order of trunk
solutions is a good fix.
Check this out:
thread690-606416 i found that by searching this forum for glare.
in that thread, they used a nokia 22 premicell as an
interface between the definity and the T1. it has
glare reduction settings (trunk seizure delay i think). there are also cisco boxs (3600 and 3640) which also have these settings. do this seem workable for me?
how do i change trunk order settings?
Enter what in the command-line?

 

[lopes1211]

The fact that you're using some channels for data shouldn't be an issue. You just need a CSU/DSU and can still terminate the remaining channels on a DS1 board in the switch. It would be a lot cleaner.

-CL

 

[Bobg1]

One thing you can try is to make sure your switch and/or Adtran are trying to grab channels in the opposite order of what you providor is using.
Lets say you are using 10 channels for voice, if you providor sends to you starting with channel 1, you would want your end to start using channel 10. This will not eliminate a glare problem but may reduce it.

 

[OldPhoneGuy]

I don't believe you can set a CO trunk group on a Rel. 6 to grab outbound trunks in a particular direction. I believe the trunks are selected on a least used basis.

 

[Bobg1]

Oldphoneguy
Does it go by least used or hunt for first available in the order listed?

 

[OldPhoneGuy]

I believe it goes by least used.