From owner-freebsd-net Thu Apr 5 10:39:24 2001 Delivered-To: freebsd-net@freebsd.org Received: from whizzo.transsys.com (whizzo.TransSys.COM [144.202.42.10]) by hub.freebsd.org (Postfix) with ESMTP id 8D39937B42C for ; Thu, 5 Apr 2001 10:39:10 -0700 (PDT) (envelope-from louie@whizzo.transsys.com) Received: from whizzo.transsys.com (localhost.transsys.com [127.0.0.1]) by whizzo.transsys.com (8.11.3/8.11.0) with ESMTP id f35Hcsn53390; Thu, 5 Apr 2001 13:38:54 -0400 (EDT) (envelope-from louie@whizzo.transsys.com) Message-Id: <200104051738.f35Hcsn53390@whizzo.transsys.com> X-Mailer: exmh version 2.3.1 01/18/2001 with nmh-1.0.4 To: Wes Peters Cc: Brett Glass , freebsd-net@FreeBSD.ORG X-Image-URL: http://www.transsys.com/louie/images/louie-mail.jpg From: "Louis A. Mamakos" Subject: Re: Transition from modem PPP to PPPoE References: <4.3.2.7.2.20010330201802.00dc8f00@localhost> <4.3.2.7.2.20010401141552.0452a6c0@localhost> <3ACBF0B6.52B99863@softweyr.com> In-reply-to: Your message of "Wed, 04 Apr 2001 22:12:38 MDT." <3ACBF0B6.52B99863@softweyr.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Date: Thu, 05 Apr 2001 13:38:54 -0400 Sender: owner-freebsd-net@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org > > The way the network is set up, not all of the nodes can > > hear one another, but all can communicate with the hub. Using PPPoE > > makes the traffic go through the hub without subnetting (which > > would require reconfiguring many machines, some of which I do > > not administer). Could you suggest a better solution? > > Sounds like an interesting network configuration. I don't know of a tunnel > program like I described above, but it would be pretty simple to develop > one using the tun device in FreeBSD. If you don't have FreeBSD at both > ends, PPPoE or another tunnelling application probably is your best choice. > It would be worth searching for a solution with less overhead than PPPoE. It's hard to imagine how PPPoE is going to add more overhead than, e.g., 20 bytes for IP-in-IP. This is an interesting application for PPPoE, which I don't think was anticipated in the initial design, but it sure seems like it would work. A question you have to ask yourself is by what metric do you measure "overhead?" Is it bytes on the wire, CPU cycles in the boxes at the ends, or administrative "costs" in operating a system. Various schemes each will have their own characteristics for each of these metrics. I've never thought that the 4 bytes of overhead per PPPoE frame was terribly inefficient, compared to, say, IP-in-IP with another 20 byte IP header. But I'm certainly not arguing that a choice of technology be made on simply the number of bytes on the wire; there are other things to consider as well. louie To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-net" in the body of the message