Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!zaphod.mps.ohio-state.edu!mips!pacbell.com!perl
From: perl@PacBell.COM (Richard Perlman)
Newsgroups: comp.sys.mac.comm
Subject: Re: line sharing (was: PacerTerm announcement)
Message-ID: <1991Jun7.045736.8108@PacBell.COM>
Date: 7 Jun 91 04:57:36 GMT
References: <55534@nigel.ee.udel.edu> <11884@hub.ucsb.edu> <27@ryptyde.UUCP>
Sender: news@PacBell.COM (Pacific Bell Netnews)
Organization: Pacific Bell - Financial Management
Lines: 23

In article <27@ryptyde.UUCP> dant@ryptyde.UUCP (Daniel Tracy) writes:
>...There is a physical limit stating you cannot open two different 
> channels on the same line (unless you're using ISDN!). 

Not quite true.  Using Data-Over-Voice (DOV) technology you can
run up to 19.2 async or 64kbs sync on top of a voice line.  Most
phone companies (at least the RBOCS) offer (or offered) a central
office based "LAN" using DOVs and (in most cases) AT&Ts DataKit VCS
(Virtual Circuit Switch) although Pacific Bell uses a Gandalf
product. 

Streching the point further, UNIX Layers and "uw" both offer the
capability to multiplex multiple "logical sessions over a single
line.  And AT&T offers a number of terminals (going back to the
BLIT) that have similar "smart" features (when connected to the
right host)


--
"What is politics, after all, but the compulsion to peside over
property and make other people's decisions for them." Tom Robbins
                               --  --
Richard Perlman   |*|  perl@pbseps.sf180.pacbell.com  |*|  (415) 545-0233