Path: utzoo!telecom-request
Date: 21 Jun 91 19:29:03 GMT
From: Dick Jackson <riacs!rutgers!ttidca.tti.com!jackson@decwrl.dec.com>
Newsgroups: comp.dcom.telecom
Subject: Re: What The Heck is "Fiber Optic Quality" Anyway?
Message-ID: <telecom11.482.8@eecs.nwu.edu>
Organization: Citicorp/TTI, Santa Monica
Sender: Telecom@eecs.nwu.edu
Approved: Telecom@eecs.nwu.edu
X-Submissions-To: telecom@eecs.nwu.edu
X-Administrivia-To: telecom-request@eecs.nwu.edu
X-Telecom-Digest: Volume 11, Issue 482, Message 8 of 9
Lines: 35

In article <telecom11.472.9@eecs.nwu.edu> Jeff Carroll <ssc-vax!carroll@
cs.washington.edu> writes:

and

> In article <telecom11.471.2@eecs.nwu.edu> ivgate!macnet!jim.redelfs@
> writes:

>>> as I understand it, virtually all long distance calls are sent in a
>>> digital format.

>	While Barry Margolin made a good point about noisy cable and
> error rates, I've never *noticed* any impairments on copper-carried
> digital lines, and I'd assert that you can't actually *hear* the
> difference.

How about this for a summary of "fiber quality"? If your call is sent
over an all digital path AND IF all the facilities are working to
spec, you will experience a near perfect performance whether the
transmission is on fiber, wire or microwave (digital microwave of
course).

Older digital systems (e.g.  T1) often did not perform to spec all the
time and did not have automatic monitoring, therefore they could be
left in service in degraded mode.  I believe that PART of the
development of the phone system to provide the very low error rates
characteristic of fiber results from the installation of continuous
quality monitoring (such as ESF).

In other words fiber is no better than other MODERN digital facilities.


Dick Jackson