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To: Eivind Eklund <perhaps@yes.no>
cc: Brian Somers <brian@FreeBSD.ORG>, hackers@FreeBSD.ORG
Subject: Re: cvs commit: src/usr.sbin/ppp lcp.c 
In-reply-to: Your message of "Mon, 22 Sep 1997 02:34:10 +0200."
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Date: Mon, 22 Sep 1997 02:09:08 +0100
From: Brian Somers <brian@awfulhak.org>
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> > 
> > brian       1997/09/21 16:02:38 PDT
> > 
> >   Modified files:        (Branch: RELENG_2_2)
> >     usr.sbin/ppp         lcp.c 
> >   Log:
> >   MFC: Sleep for a second before sending the first LCP
> >        config request.  This stops us from squirting stuff
> >        down a line that still has ECHO turned on because the
> >        peer hasn't had a chance to start yet.
> >        Lead to the cause by:	Greg Lehey <grog@lemis.com>
> 
> Isn't detecting this what the magic number more-or-less was introduced
> for?  You can catch looping LCP-negotiation by looking for the same
> magic number, and it really seems a pity to waste a second on
> connection, as this could be running on really fast links (like TCP or
> ISDN links).  Besides, if the other end is slow, 1 second might not be
> enough.

When we connect to a machine that is running a bit slow, the 
client-side ppp manages to send 6 LCPs, receive the same 6 back (due 
to echo being on) and give up - all before the server-side ppp gets 
to turn ECHO off.

Maybe I should incrementally "back out" when receiving config 
requests w/ the same magic - ie, wait .2 seconds after the first dup 
magic, .4 after the second etc.

> Eivind.

> >   Sleep for a second before sending the first LCP
> >   config request.  This stops us from squirting stuff
> 
> Don't forget that some boxes, if you wait a second or more, will fall
> back into ``terminal server'' mode, and then the user gets hosed.  The
> Shiva LanRover Access Switch is one such box in wide circulation.

Hmm, looks like the incremental backout may be a better idea.

> -GAWollman
-- 
Brian <brian@Awfulhak.org>, <brian@FreeBSD.org>, <bri@OpenBSD.org>
      <http://www.Awfulhak.org>
Don't _EVER_ lose your sense of humour....