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Incoming and Outgoing Calls

Posted by rockinthesixstring on Wed, 05/28/2008

I had a strange thing happen today. I was making a call out and someone was calling in at the exact same time. Instead of the calls going past one another in the system, we ended up talking to one another.

How can I resolve this?


Submitted by eeman on Wed, 05/28/2008 Permalink

this is called 'glare' and analog lines are subject to it. There are some things you can do to avoid it. How many analog lines do you have? Lets say you have 4 and on inbound they come in ascending order..

1, 2, 3, 4

instead of having your zap trunk named g1 (which is a Zap/g1 in the dial statement) name it G1 (as in Zap/G1). The capitol G makes it start with the highest number first. It helps reduce glare.

Loop Start and Kewl start are always vulnerable to glare as is E&M T-1's.

Ground start isnt because it has to ground the tip before going off hook to notify the other end its about to place a call.

PRI likewise negotiates a channel with both ends before sending the call. Its still best practice to receive calls in ascending order and place them in decending.