[157103] in North American Network Operators' Group
Re: IPv4 address length technical design
daemon@ATHENA.MIT.EDU (Fred Baker (fred))
Fri Oct 5 21:06:54 2012
From: "Fred Baker (fred)" <fred@cisco.com>
To: Barry Shein <bzs@world.std.com>
Date: Sat, 6 Oct 2012 01:06:06 +0000
In-Reply-To: <20591.28278.961557.174820@world.std.com>
Cc: John Levine <johnl@iecc.com>, "<nanog@nanog.org>" <nanog@nanog.org>
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org
On Oct 5, 2012, at 4:34 PM, Barry Shein wrote:
> Well, XNS (Xerox Networking System from PARC) used basically MAC
> addresses. Less a demonstration of success than that it has been
> tried. But it's where ethernet MAC addresses come from, they're just
> XNS addresses and maybe this has changed but Xerox used to manage the
> master 802 OUI list and are assigned OUIs 000000...000009. Not
> insignificant in their effect.
You need a memory refresh. XNS used a three part address: network number, h=
ost identifier, and socket number. "Socket" was in essence the TCP/UDP Port=
Number. the host identifier was as you say a 48 bit number and generally t=
ook as its value the MAC address on one of the interfaces - and the same MA=
C address was used on all interfaces. Hence, no need for ARP/ND. The networ=
k number was a 32 bit number assigned to a LAN subnet. A multihomed host es=
sentially implemented ILNP.=20
The issue with the network number was, of course, that it couldn't be aggre=
gated in any useful way. But XNS was not ethernet bridging on a wide scale.=
