Subject: Re: dial-up over regular ethernet IP (xs4)
To: Rogier Krieger <>
From: Bill Studenmund <>
List: tech-net
Date: 06/05/2002 10:00:31
On Wed, 5 Jun 2002, Rogier Krieger wrote:

> Hi everyone,
> this may be a slightly odd question, but I figured it might best be
> asked here. I'd like to establish a PPP-like session over a regular
> ethernet IP connection.
> I have a setup in mind as follows:
> 	The Internet -------> PPP dial-in server
> 	        |
> 	        | (IPv4)
> 	        |
> 	upstream connection
> 	        |
> 	        | (IPv4 / Ethernet)
> 	        |
> 	NetBSD box
> In this scheme, I'd like to maintain and use both the regular
> ethernet link from the NetBSD box as well as obtain an address
> through a PPP-like server (that also serves regular modem dial-ins).
> I intend to use latter PPP-like link as a route for only a single
> domain (say '') and use the regular ethernet link for
> all other traffic.

Does it have to be PPP?

Yes, you can do stuff like this. As for the last point, a route covering
the university IP range and going through your tunnel will work fine.

> Is there a solution for this? I tried finding out more about PPPoE
> (of which the name suggests it can do the trick), but I'm unsure
> whether I can direct such a PPP-session over intermediate routers to
> the IP address of the PPP dial-in server.

pppoe is ppp on top of raw ethernet, not on top of IP. So it won't do

The easiest thing is if you have a NetBSD box inside the university. Then
a lot of the things Itojun mentioned will work. Running an IPsec tunnel
and a gif on top of it would be my vote. :-)

Take care,