Subject: Re: no v4, slip this time
To: der Mouse <mouse@Rodents.Montreal.QC.CA>
From: Michael Richardson <>
List: tech-net
Date: 07/17/2002 19:42:49

>>>>> "der" == der Mouse <mouse@Rodents.Montreal.QC.CA> writes:
    >> But, the IP encapsulation stuff can be pretty simple - why not just
    >> run PPP without LCP, etc. - just use PPP encapsulation.  At least
    >> stuff like tcpdump will understand it.

    der> That's an attractive option; I didn't know it could be done.  How
    der> would 
    der> I go about it?

    der> It's not clear whether you're proposing I use some (hidden?) option to
    der> pppd that bypasses most of its code, or write an slattach-alike that

  I know of no such option, but you could certainly add on.
  Knowing you, I'd go the "slattach" way. The kernel then does the data
encap/decap for you.

    der> Perhaps I'm just exposing my ignorance of the PPP implementation here?

  Go read the spec. PPP, particularly sync-PPP, is VERY simple.

  The 1/2-byte protocol number encoding is a little bizarre at first, but
there are some good noise-resistance reasons there. This is Bill Simpson at
his best.

]       ON HUMILITY: to err is human. To moo, bovine.           |  firewalls  [
]   Michael Richardson, Sandelman Software Works, Ottawa, ON    |net architect[
] |device driver[
] panic("Just another NetBSD/notebook using, kernel hacking, security guy");  [

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Comment: Finger me for keys