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From: ronald@robobar.co.uk (Ronald S H Khoo)
Newsgroups: comp.dcom.modems
Subject: Re: LAP-M frame formatting
Message-ID: <1991Mar18.181406.18104@robobar.co.uk>
Date: 18 Mar 91 18:14:06 GMT
References: <5098@mindlink.UUCP> <3853.27de1d8e@hayes.uucp>
Organization: Robobar Ltd., Perivale, Middx., ENGLAND.
Lines: 17

tnixon@hayes.uucp writes:

> LAPM, like MNP3, LAPB, LAPD, and many other protocols, is based on 
> the High-level data link control (HDLC) frame format specified in 
> ISO 3309.  This uses a particular sequence of bits (01111110), known 
> as a "flag", to delimit frames.

Toby, the Internet RFC (1171) for their point-to-point protocol describes
an async addendum to 3309 as PDAD1/1984.  Do you know if this ever
passed, and if any of your (or anyone else's :-) modems will
convert sync/async this way, including conversion of the sync
bit-stuffing <-> the async character stuffing, maybe + data rate conversion
as well ?  Might be damned useful that, given the expense and non-standardness
of synchronous serial cards for PCs ...

-- 
Ronald Khoo <ronald@robobar.co.uk> +44 81 991 1142 (O) +44 71 229 7741 (H)