From owner-freebsd-hackers Wed Oct 7 12:59:32 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id MAA06774 for freebsd-hackers-outgoing; Wed, 7 Oct 1998 12:59:32 -0700 (PDT) (envelope-from owner-freebsd-hackers@FreeBSD.ORG) Received: from david.siemens.de (david.siemens.de [192.35.17.14]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id MAA06745 for ; Wed, 7 Oct 1998 12:59:27 -0700 (PDT) (envelope-from andre.albsmeier@mchp.siemens.de) X-Envelope-Sender-Is: andre.albsmeier@mchp.siemens.de (at relayer david.siemens.de) Received: from mail.siemens.de (salomon.siemens.de [139.23.33.13]) by david.siemens.de (8.9.1a/8.9.1) with ESMTP id VAA11920 for ; Wed, 7 Oct 1998 21:59:10 +0200 (MET DST) Received: from curry.mchp.siemens.de (daemon@curry.mchp.siemens.de [146.180.31.23]) by mail.siemens.de (8.9.1a/8.9.1) with ESMTP id VAA05807 for ; Wed, 7 Oct 1998 21:59:11 +0200 (MET DST) Received: (from daemon@localhost) by curry.mchp.siemens.de (8.8.8/8.8.8) id VAA18220 for ; Wed, 7 Oct 1998 21:59:12 +0200 (CEST) From: Andre Albsmeier Message-Id: <199810071959.VAA02775@internal> Subject: Re: How to send data between two network cards directly? In-Reply-To: <199810071518.QAA08692@labinfo.iet.unipi.it> from Luigi Rizzo at "Oct 7, 1998 4:18:42 pm" To: luigi@labinfo.iet.unipi.it (Luigi Rizzo) Date: Wed, 7 Oct 1998 21:59:09 +0200 (CEST) Cc: hackers@FreeBSD.ORG X-Mailer: ELM [version 2.4ME+ PL43 (25)] MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Content-Transfer-Encoding: 7bit Content-Transfer-Encoding: 7bit Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG > > > > together via 10Base2. I would like to send data from one > > > > machine two the other without doing IP or any other > > > > protocol. > ... > > OK, maybe I desribed it in a wrong way. I would like to use > > the most basic protocol that is available. No overhead, > > no error correction, no nothing... > ... > > I have got two wireless-lan-like developer boxes. They got each an UTP > > port and transmit data via a direct spread spectrum frequency hopping > > protocol. We have two compare their performance, errors and reliabilty > > with other, for example RS232 or S0 bus based, boxes. They run the ethernet > > protocol (ok, this is the lowest level protocol, I have to use) and I would > > like to transmit data without running TCP,UDP or something else. > > then for your purposes, UDP or raw ethernet packets are absolutely > equivalent. I think I will stick with the raw packets first and see how it is working. I still don't know exactly what I have to expect since I don't have much infos about the internal of these boxes. These are only some experimental test and, as you can imagine, I will have to do some comparisons with the RS232 and S0 bus stuff so it's actually comparing apples with pears as we say in germany :-) > > if you really want to see things in detail you might try to disable UDP > checksums (i think this is a socket-level option, isn't it ?) > or even pass up bad frames from the ethernet driver (either > use bpf, or play with the ethernet driver) Yes the bpf was also coming on my mind but I still haven't got much experience with it (from a programers point of view) and I have to get this thing running in a short time. > > cheers > luigi Thanks a lot for your help, -Andre To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message