From owner-freebsd-security Thu Sep 9 12:57: 8 1999 Delivered-To: freebsd-security@freebsd.org Received: from gndrsh.dnsmgr.net (GndRsh.dnsmgr.net [198.145.92.4]) by hub.freebsd.org (Postfix) with ESMTP id D6BD215642 for ; Thu, 9 Sep 1999 12:57:05 -0700 (PDT) (envelope-from freebsd@gndrsh.dnsmgr.net) Received: (from freebsd@localhost) by gndrsh.dnsmgr.net (8.9.3/8.9.3) id MAA18901; Thu, 9 Sep 1999 12:53:26 -0700 (PDT) (envelope-from freebsd) From: "Rodney W. Grimes" Message-Id: <199909091953.MAA18901@gndrsh.dnsmgr.net> Subject: Re: Lisen only NIC In-Reply-To: <13779.936905560@verdi.nethelp.no> from "sthaug@nethelp.no" at "Sep 9, 1999 09:32:40 pm" To: sthaug@nethelp.no Date: Thu, 9 Sep 1999 12:53:26 -0700 (PDT) Cc: imp@village.org, jwyatt@rwsystems.net, Goran.Lowkrantz@infologigruppen.se, freebsd-security@FreeBSD.ORG X-Mailer: ELM [version 2.4ME+ PL54 (25)] MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-freebsd-security@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org > > I've seen in other discussions that while you could do this with the > > AUI based ethernet cards, you can't do this with 10base2 or 10base-t > > cards. Thinnet is obvious... But the 10-base-t/100-base-t cards need > > the xmit lines to negotiate speed settings with the hub. Can anybody > > confirm this? > > Not just for the negotiation, but also to keep the link up. There are > link pulses sent at regular intervals. If these are not received, the > link is detected as being down. Can you confirm for me that the link pulses are actually a function of the MAU/MII and not the NIC chip. I don't recall seeing anything in any NIC chip data sheet that talks about these. I don't have any current MAU/MII data sheets. > > It's possible to "cheat" on this with some active electronics. Anzen > makes a "receive only" cable, see > > http://www.anzen.com/afj/afj_faq.html#anchor157338 Back to back MAU's with the XMIT pair left out perhaps??? -- Rod Grimes - KD7CAX - (RWG25) rgrimes@gndrsh.dnsmgr.net To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-security" in the body of the message