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Date: Thu, 23 Jan 1997 19:47:22 -0600
To: Brett_Glass@infoworld.com, gurney_j@resnet.uoregon.edu,
        lenc@earth.infinetconsulting.com
From: Allen Hyer <allenh@wtrt.net>
Subject: Re: 56K vs X2?
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        freebsd-isp@FreeBSD.org, freebsd-hardware@FreeBSD.org
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At 04:38 PM 1/23/97 PST, Brett_Glass@infoworld.com wrote:
>> since the originating data was straight PCM codes, the digital to analog
>> conversion should theoretically not change the data.
>
>Even if you send straight PCM codes, you have no control over bit robbing
>on switched circuits. (You can get DEDICATED clear channel T1, but to my
>knowledge, you can't rely on clear channel through a phone switch.)

I'm not an expert in telco technology, but if it makes any difference, on
the USR total control system, you must use "trunk-side" T1's.  Your other
option is to use ISDN-PRI.

Allen Hyer
System Administrator
West Texas Rural Telephone