From owner-freebsd-net Thu Jul 29 20:16:29 1999 Delivered-To: freebsd-net@freebsd.org Received: from khavrinen.lcs.mit.edu (khavrinen.lcs.mit.edu [18.24.4.193]) by hub.freebsd.org (Postfix) with ESMTP id E8E251566E for ; Thu, 29 Jul 1999 20:16:15 -0700 (PDT) (envelope-from wollman@khavrinen.lcs.mit.edu) Received: (from wollman@localhost) by khavrinen.lcs.mit.edu (8.9.1/8.9.1) id XAA15418; Thu, 29 Jul 1999 23:15:48 -0400 (EDT) (envelope-from wollman) Date: Thu, 29 Jul 1999 23:15:48 -0400 (EDT) From: Garrett Wollman Message-Id: <199907300315.XAA15418@khavrinen.lcs.mit.edu> To: Wes Peters Cc: net@FreeBSD.ORG Subject: Re: cvs commit: src/release/sysinstall tcpip.c In-Reply-To: <37A0F5C9.48F4A442@softweyr.com> References: <199907290226.WAA11541@khavrinen.lcs.mit.edu> <199907291434.KAA13492@khavrinen.lcs.mit.edu> <37A0F5C9.48F4A442@softweyr.com> Sender: owner-freebsd-net@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org < said: > The VLANs are seperate networks which happen to share the same physical > space, that's why they're called Virtual LANs. What Xylan^H^H^H^H^HPa^H^HAlcatel happens to mean by ``VLAN'' is not necessarily the same thing as other vendor means, is not necessarily the same as the abstract model of IEEE 802.1Q. Aren't standards wonderful? In the hardware we use, VLANs are a strict superset of (logical) router interfaces -- that is to say, you can't route packets except between two VLANs, and you can't comunicate between two VLANs except through a router interface. Billf was suggesting that every host be in its own VLAN, which of course would mean that it could not talk to anything else without the intercession of a router interface, which in turn requires an IP subnet of at least minimum (/30) size, which would waste 75% of one's address space. I pointed out in response to Bill that, while our Lab does in fact have oceans of globally-routeable address space, we could not in practice give a /30 to each one of our four-thousand-someodd machines because our switches support a maximum of 256 router interfaces. -GAWollman -- Garrett A. Wollman | O Siem / We are all family / O Siem / We're all the same wollman@lcs.mit.edu | O Siem / The fires of freedom Opinions not those of| Dance in the burning flame MIT, LCS, CRS, or NSA| - Susan Aglukark and Chad Irschick To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-net" in the body of the message