[Asterisk-Users] Freak incidents, who's to blame?

[Alexander Lopez]

-----Original Message-----
From: asterisk-users-bounces at lists.digium.com
[mailto:asterisk-users-bounces at lists.digium.com] On Behalf Of Eric
Wieling aka ManxPower
Sent: Tuesday, May 03, 2005 12:34 PM
To: Asterisk Users Mailing List - Non-Commercial Discussion
Subject: Re: [Asterisk-Users] Freak incidents, who's to blame?

Ryan Courtnage wrote:
> Hello all,
> 
> Everyone has probably experienced this at some point in the past:
> You pick up your analog phone.  Rather than hearing dialtone, you are

> connected with someone who has just called you.  Neither you nor them

> heard a ring.
> 
> Maybe it's just me, but it seems these "freak incidents" would occur  
> more frequently years ago, than now.
> 
> I've now experienced this a couple of times with an * system (TDM400p
- 
> quad FXO):
> A SIP exten dials digits which are answered by a Zap trunk.  As soon
as 
> Zap answers, the SIP extension is connected with an inbound (PSTN)  
> caller (who was expecting to hear an IVR).
> 
> My questions are:  Who's to blame (telco, tdm card, * config,  
> gremlins)?  Is this avoidable?

It's called "glare".


All elaborate on 'GLARE'

Think about opening your front door on your way out just before the
person gets a chance to ring the doorbell. Bam, there you are just
"GLARING" at on e another.

Glare could probably be reduced if you ALWAYS walked out the back door
and those coming to visit you go to the front. You can set * to select
lines in an order opesite than the way they roll over.  For example our
lines ring in ascending order line 1, then 2, 3,4,5, etc. If you set the
PBX to grab line in decending order you will make outgoing calls on
lines 5,4,3,2,1, decreasing the chances that * will open a ZAP door and
find someone 'standing' there....


Hope this helps.