From owner-freebsd-net  Thu Nov 16 15:39:48 2000
Delivered-To: freebsd-net@freebsd.org
Received: from mail.interware.hu (mail.interware.hu [195.70.32.130])
	by hub.freebsd.org (Postfix) with ESMTP id 7920D37B4C5
	for <freebsd-net@freebsd.org>; Thu, 16 Nov 2000 15:39:45 -0800 (PST)
Received: from dakar-18.budapest.interware.hu ([195.70.51.82] helo=elischer.org)
	by mail.interware.hu with esmtp (Exim 3.16 #1 (Debian))
	id 13wYd4-0003fN-00; Fri, 17 Nov 2000 00:39:42 +0100
Message-ID: <3A14701F.4CF92AFB@elischer.org>
Date: Thu, 16 Nov 2000 15:39:11 -0800
From: Julian Elischer <julian@elischer.org>
X-Mailer: Mozilla 4.7 [en] (X11; U; FreeBSD 5.0-CURRENT i386)
X-Accept-Language: en
MIME-Version: 1.0
To: Falco Krepel <krepel@fokus.gmd.de>
Cc: "freebsd-net@FreeBSD.ORG" <freebsd-net@FreeBSD.ORG>
Subject: Re: New Protocol over Ethernet
References: <3A142E0C.1B1D18DD@fokus.gmd.de>
Content-Type: text/plain; charset=iso-8859-15
Content-Transfer-Encoding: 7bit
Sender: owner-freebsd-net@FreeBSD.ORG
Precedence: bulk
X-Loop: FreeBSD.org

Falco Krepel wrote:
> 
> Hi,
> 
> I want to implement my own protocol on top of ethernet. This protocol
> should should not influence other protocols running on the system. So I
> must distinguish my own frames from other frames.
> 
> Because this is my first time to implement such a protocol on FreeBSD I
> am not sure how I can do this. I have read some documentation about
> interprocess communication within FreeBSD, the TCP/IP illustrated book,
> ... Furthermore I study the BSD source code around network
> communication. But until now it is not clarify how I can do this in the
> best way.
> 
> If I understood it right, three approaches exists:
> 
> 1. I creat with netgraph a hook over ther ethernet interface. With this
> solution I am not shure how much overhead this adds because it could be
> possible that this runs into timing problems.
> 

There will be no more timing load that any other scheme you can think
of.
Netgraph is very efficient. 

it would help a bit if you gave more specific information as to the 
characterisitics of the protocol you want.

> 2. I attach direct to the ethernet interface. This means I must add a
> new protocol class to get only my own frames. Is that right?

Basically you will need to alter the ethernet driver framework.
I did this several times and it is why I wrote netgraph.
Netgraph can already deliver the packets to you..

> 
> 3. I use the DL interface with a socket. About the DL interface I
> haven't found any information how I can use this interface.
> 
> Now my questions:
> 
> - Are the three ways correct or I did misunderstand something?
> - Does exist an implementation which could help me to find the solution?
> - Has anybody experience with such an implementation?
> 

many people have done this..



> I hope somebody can help me. I am also happy about some hints about good
> literature helping me to solve this problem.
> 
> Thanx in advanced
> 
> Falco
> 
> --
> Falco Krepel                    Phone:  +49-(0)30 - 34 63 - 7 276
> GMD-FOKUS                       Fax:    +49-(0)30 - 34 63 - 8 276
> Kaiserin-Augusta-Allee 31       e-mail: krepel@fokus.gmd.de
> 10589 Berlin                    WWW:    http://www.fokus.gmd.de/usr/krepel
> 
> To Unsubscribe: send mail to majordomo@FreeBSD.org
> with "unsubscribe freebsd-net" in the body of the message

-- 
      __--_|\  Julian Elischer
     /       \ julian@elischer.org
    (   OZ    ) World tour 2000
---> X_.---._/  presently in:  Budapest
            v


To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-net" in the body of the message