Path: utzoo!mnetor!uunet!husc6!cmcl2!nrl-cmf!ames!oliveb!jerry
From: jerry@oliveb.olivetti.com (Jerry Aguirre)
Newsgroups: comp.dcom.modems
Subject: Re: Telebit requests Information
Message-ID: <17957@oliveb.olivetti.com>
Date: 12 Mar 88 00:27:04 GMT
References: <265@telebit.UUCP>
Reply-To: jerry@oliveb.UUCP (Jerry Aguirre)
Organization: Olivetti ATC; Cupertino, Ca
Lines: 24
Keywords: leased-line modem PEP synchronous
Summary: synchronous 4 wire full-duplex operation

In article <265@telebit.UUCP> modems@telebit.UUCP (Modem Mail Account) writes:
>We here at Telebit are very interested in the USENET community at large,
>and would like to hear what features and functionality you'd like to see
>in modems, particularly for the Unix environment. If any of you have any

I think a PEP modem for 4 wire leased line use would be nice.  Given
separate transmit and receive pairs it should run in true full duplex
mode.  Higher speed lines are usually configured for synchronous
operation so the interface should be synchronous or have that option.
Better yet, how about separate async and sync interfaces.  That way you
could still configure the modem using an async terminal.

I realize that there are leased line modems capable of speeds as fast as
PEP mode but they don't offer the same features.  If the line quality
deteriorates they fall back in huge increments.  They do not provide an
error free packetized link;  the data communications hardware/software
has to deal with the errors.  I doubt they are as forgiving of line
problems.  Finally, they are expensive.

The idea of a PEP based modem sliding its synchronous interface clock
rate up and down to maximize thruput for the current line quality
appeals to me.  (Look ma, no flow control!)

				Jerry Aguirre