From owner-freebsd-stable Sat Dec 21 17:57:32 1996 Return-Path: Received: (from root@localhost) by freefall.freebsd.org (8.8.4/8.8.4) id RAA13257 for stable-outgoing; Sat, 21 Dec 1996 17:57:32 -0800 (PST) Received: from eldorado.net-tel.co.uk ([193.122.171.253]) by freefall.freebsd.org (8.8.4/8.8.4) with SMTP id RAA13252; Sat, 21 Dec 1996 17:57:27 -0800 (PST) From: Andrew.Gordon@net-tel.co.uk Received: (from root@localhost) by eldorado.net-tel.co.uk (8.6.12/8.6.10) id BAA23200; Sun, 22 Dec 1996 01:56:52 GMT Received: from "/PRMD=NET-TEL/ADMD=GOLD 400/C=GB/" by net-tel.co.uk (Route400-RFCGate); Sun, 22 Dec 96 1:55:15 +0000 X400-Received: by mta "eldorado" in "/PRMD=net-tel/ADMD=gold 400/C=gb/"; Relayed; Sun, 22 Dec 96 1:55:15 +0000 X400-Received: by mta "net-tel cambridge" in "/PRMD=net-tel/ADMD=gold 400/C=gb/"; Relayed; Sun, 22 Dec 96 1:55:13 +0000 X400-Received: by "/PRMD=NET-TEL/ADMD=Gold 400/C=GB/"; Relayed; Sun, 22 Dec 96 1:55:13 +0000 X400-MTS-Identifier: ["/PRMD=NET-TEL/ADMD=Gold 400/C=GB/";hst:21271-961222015513-12AB] X400-Content-Type: P2-1984 (2) X400-Originator: Andrew.Gordon@net-tel.co.uk Original-Encoded-Information-Types: IA5-Text X400-Recipients: non-disclosure:; Date: Sun, 22 Dec 96 1:55:13 +0000 X400-Content-Identifier: Re(2): User ppp Message-Id: <"84a-961222015526-FEB1*/G=Andrew/S=Gordon/O=NET-TEL Computer Systems Ltd/PRMD=NET-TEL/ADMD=Gold 400/C=GB/"@MHS> To: list:; Cc: freebsd-questions@freebsd.org, freebsd-current@freebsd.org, freebsd-stable@freebsd.org In-Reply-To: Subject: Re(2): User ppp not hanging up modem. Sender: owner-stable@freebsd.org X-Loop: FreeBSD.org Precedence: bulk > On Sat, 21 Dec 1996 dicen@hooked.net wrote: > > Nate Williams wrote: > > > That's *NOT* the correct thing. What happens when for some reason > > > PPP happens to send the sequence '+++' to the modem? All of a sudden > > > it'll drop into command mode and you're screwed. User-PPP (as well as > > > all other PPP/SLIP implementations I've worked with) assumes that > you've > > > disabled the escape sequence at least temporarily. > > > > > Interesting. But, what exactly is the prabobalitity of that? I will have > > think about this one. > > Note that the standard command "&D3" tells the modem to reset itself when > DTR drops. Nate's right, this _is_ standard. What he missed was that > Hayes modems (Hayes originated the protocol that's now a defacto standard) > used to get around the +++ transparency issue by requiring a 2 second dead > time (either before or after the +++ code, I forget which). Before _and_ after - hence you are safe even if a packet begins or ends with "+++". > Hayes > patented that delay, I think, which is why modems don't use it anymore. Good modems still do (USR Courier for example) - presumably having licenced with Hayes. Some junk modems don't.....