DSL with PBX question

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daraxta

DSL with PBX question

Post by daraxta »

Hi,

Does DSL work with a PBX system?

Thanks
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macyh
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Joined: Thu Mar 28, 2002 11:44 am
Location: Cleveland, Ohio USA

Post by macyh »

This is rather a broad question. I'll give some general answers in an attempt to be helpful.

You cannot pass the ADSL thru the PBX, the ADSL signal must be split off from the phone line, typically by using an ADSL splitter. A microfilter installed between the phone line demarc and the PBX input jack will also work.

ADSL can technically operate on any conventional loop start telephone line. Some PBX outside lines are ground start, ADSL will not work properly with ground start lines.

Many telco's will not provision ADSL on a phone line terminating on a PBX or that is part of a "multiline hunt group" (policy varies by telco, ask). Most businesses just put the ADSL on a fax or modem line instead; again a splitter or microfilter is required.

Telco's will not provision ADSL on other types of phone lines, such as off premise extensions.

If you are trying to use a extention line behind a pbx to bring ADSL to your desktop, it won't work. You need a line that runs all the way back to the telco central office. Your PBX extention only goes to the PBX room.

Not what you needed? Provide more details of what you are trying to do, you'll get a more detailed answer.
Macy Hallock from APK Net, Inc. in Cleveland, Ohio USA
jim1133
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Joined: Tue Jan 30, 2001 12:00 am
Location: Lexington, MA

Post by jim1133 »

Hi Macy,
I was a PBX repairman 50 years ago and you impressed me as one who knows the telco business. Not many are familiar with Ground start/Loop start, etc.
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macyh
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Joined: Thu Mar 28, 2002 11:44 am
Location: Cleveland, Ohio USA

Post by macyh »

Originally posted by jim1133
Not many are familiar with Ground start/Loop start, etc.
Not many maintained No.1 SxS, Leich, North CX500 CO switches, plus Ericsson, Leich, AE, NE, WECO, TIE, Rolm, Chestel and TR-32 PBX's, either. Not to mention Panhandle LN, Lenkurt, AE and WECO carrier systems. (This is from a past life, though I have been involved in telecom and datacom all my life. Have I dated myself yet?)

I own an ISP now, we provision and install quite a few ADSL lines each month. We have to assist, reconfigue and repair inside wiring all the time, as well as install our own T1 demarc extensions. You just can't escape the plant and cabling issues with any form of telecom work.

And most people still have no idea of why we still use ground start lines on PBX's, either. (Hint: Glare) (Although I'm getting spoiled using ISDN PRI these days.)
Macy Hallock from APK Net, Inc. in Cleveland, Ohio USA
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