[Asterisk-Users] Best echo-free and trouble-free system?

[Raymond McKay]

----- Original Message ----- 
From: "Barton Hodges" <barton at gcmcomputers.com>
To: <asterisk-users at lists.digium.com>
Sent: Wednesday, April 28, 2004 1:18 PM
Subject: [Asterisk-Users] Best echo-free and trouble-free system?

> What is the best setup for ensuring an echo-free and trouble-free
> system?

I regularly build systems for clients based off of Asterisk.  If you want to
be guaranteed of no echo whatsoever, then going the analog route seems the
way to go for now.  My small office configurations usually utilize a Dell
Optiplex GX270 as the actual phone system server and a T100P connected to an
Adtran Channel Bank (TA750) with 1 FXO and 3 FXS Cards.  The PowerTouch 390
phones work really well, just make sure you get them though one of the
distributors listed on Digium's site unless you have strong familiarity with
ADSI programming.  You can then run VoIP (I prefer Cisco) phones for offsite
phones as necessary.

Assuming you need a full 12 phones, the system usually runs about $5000
cost.  The Avaya Partner system, a very popular system for small businesses,
runs about the same price when you add in all the messaging and call routing
modules but of course doesn't support VoIP.

Here is a complete list of Parts I use on a standard system

Optiplex GX270
***1 600VA or higher UPS *** VERY IMPORTANT - You don't want bad power to
kill the system
Digium T100P T1 Interface
Adtran TA750 /w 12 FXS - 3 Cards (Part # 4175002L3#AC)
Adtran TA750 QUAD FXO Card (Part # 1175407L2)
5' Female to Female Amphenol Cable
24 Port Telephone Patch Panel (2 conductor) - See
http://www.phonegeeks.com/patpanwit25p.html
1 24 Port Cat5e Patch Panel
Cat5e Cable and RJ45 Jacks (To run between the Desks and Cat5e Patch Panel)
Cat3 Cable and RJ11 ends (to patch between the Cat5e panel and the Telephone
Panel)
Astra PowerTouch 390 Phones (or whatever phone client likes)


Some Additional Advice:  Always run Cat5e from the desk to the Cat5e patch
panel.  This way, if echo-cancellation ever becomes flawless in Asterisk,
you have a easy migration path to VoIP phones.  I generally do create Cat3
jumpers from the Cat5e patch panel to the Telephone Patch panel.  For those
of you who don't know, RJ11 connectors will fit and work in a RJ45 jack just
fine.  The same goes for the patch cord from the telephone to the Cat5e
phone jack deskside.

Mind you, this is not the solution for those looking for the "cheap" way
out.  If they want a flawless system that rivals and exceeds the reliability
of what is in the market today, then they have to be willing to pay for it.
I have about 10 systems in production like this at various clients.  To
date, I have not had any issues with any of them.  This configuration is of
course my opinion of the best configuration.  As the saying goes, your
mileage may vary.

Raymond McKay
President
RAYNET Technologies LLC
http://www.raynettech.com
(860) 833-9720