From owner-freebsd-questions Wed Mar 28 7:36:13 2001 Delivered-To: freebsd-questions@freebsd.org Received: from chmod.ath.cx (CC2-1242.charter-stl.com [24.217.116.226]) by hub.freebsd.org (Postfix) with ESMTP id E956D37B72B for ; Wed, 28 Mar 2001 07:35:54 -0800 (PST) (envelope-from ajh3@chmod.ath.cx) Received: by chmod.ath.cx (Postfix, from userid 1001) id B0D9AA91A; Wed, 28 Mar 2001 09:35:19 -0600 (CST) Date: Wed, 28 Mar 2001 09:35:19 -0600 From: Andrew Hesford To: Edward Cc: freebsd-questions@freebsd.org Subject: Re: MAC Message-ID: <20010328093519.A12297@cec.wustl.edu> References: <3AC19A18.EDCF8A4@hotmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5i In-Reply-To: <3AC19A18.EDCF8A4@hotmail.com>; from edward_gess@hotmail.com on Wed, Mar 28, 2001 at 10:00:24AM +0200 X-Loop: Andrew Hesford Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG On Wed, Mar 28, 2001 at 10:00:24AM +0200, Edward wrote: > Hello all, > How to change the MAC address in FreeBSD??? When I am creating > socket, how FreeBSD knows which network interface to > use??? How works network sniffers and how to protect myself from > them??? How works ARP on low level??? I don't understand > this because I know that it is not using TCP/IP... , but how then > data frames arrives to the host knowing only it MAC address and > more it can be changed??? Is the hosts on LAN know MAC addresses to > which they are connected??? Or just frames are > sent to all hosts on LAN and who's MAC is the same as in frame, > answers ??? > > In a word please give me some links on documetns about those > things... The MAC address of a network card is hard-wired. Occassionally, the card manufacturer will let you change a few digits, but this is dangerous and can lead to network problems. I'm not sure who grants blocks of MAC addresses to card manufacturers, it might be the FCC, or it might be ICANN. The idea behind a MAC address is to give a unique identifier to the card, so protocols like TCP can figure out where to send packets. -- Andrew Hesford ajh3@chmod.ath.cx To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message