Subject: [rbridge] Global MAC Addresses

From: uets.jmb at gmail.com (Jose Morales Barroso)
Date: Tue, 13 Mar 2007 20:07:20 +0100

Dear colleagues:

UETS/EFR architecture uses locally administered (U/L bit = 1)
MAC addresses, "taking  advantage of interface identifiers
with universal scope", as described at:

 http://www.lmdata.es/uets/draft/uets-efr-addressing.pdf

This technology permits to switch Ethernet frames at the physical
layer, making it unnecessary to use routing, bridging, or signaling
techniques. The Destination Address has the path information,
and does not need tables of switching, look-up or forwarding:

 http://www.lmdata.es/uets/draft/uets-efr-scenario-wwn.pdf

Using MAC-in-MAC or SNAP, each connection support another
Ethernet domain.  In this case, the addressing will be huge, even
bigger than IPv6, making possible to build a "Global Ethernet".

You have more information in the UETS/EFR page:

 http://www.lmdata.es/uets.htm

Jose Morales
jmb at ieee.org

Eric Gray (LO/EUS) wrote:

>> Interstingly enough, I am really sure that the IPv6 folks
>> have looked at this before.  And I am also sure that at least one
>> suggested solution has been considered.  I do not know if any (of
>> possibly many) proposals were actually adopted but, if none were,
>> it would be because the IPv6 people did not see this as a problem.
>
>AFAIK the IPv6 folks have not considered this.
>But as you pointed out, the global IPv6 addresses would still be
>globally unique since they would have different subnet prefixes.
>
> The only issue for IPv6 is that this (and host-side virtualization in
> general) means that the the semantics of the universal bit in the
> modified EUI-64 format is even weaker than before.
> But there is no protocol to date which assumes anything about the
> semantics of this bit. As RFC 4291 says:

>   The use of the universal/local bit in the Modified EUI-64 format
>   identifier is to allow development of future technology that can take
>   advantage of interface identifiers with universal scope.

>  Erik