Re: [RFC] New Driver Model for 2.5

Kai Henningsen (kaih@khms.westfalen.de)
19 Oct 2001 19:09:00 +0200


benh@kernel.crashing.org (Benjamin Herrenschmidt) wrote on 19.10.01 in <20011018220604.23253@smtp.wanadoo.fr>:

> collisions between uuid's of different devices types. In the case of
> ethernet hardware, the MAC address seems to be the best type of uuid
> available, so it would be something like "ethaddr,xx:xx:xx:xx:xx:xx",
> FireWire has a generic uuid allocation scheme as well, it could be
> "ieee1394,xxxxxx...", etc...

I have no idea what Firewire uses, but there are two generic kinds of
numbers that the IEEE allocates (actually, they're two different views on
a single id space).

Those are the MAC-48 address used by ethernet, fddi, and various other
protocols, and the EUI-64 used by more modern designs (and referenced by
IPv6; in fact, there's an algorithm that lets you create an EUI-64 from a
MAC-48 via bit stuffing).

Both of these depend on a 24 bit id called company_id or OUI which you can
buy from the IEEE for US$1.250,00 (for 16 million MAC-48's or 1 trillion
EUI-64's).

The list of public OUIs is at <URL:http://standards.ieee.org/regauth/oui/
oui.txt> (there are "unlisted numbers" in that namespace, too).

Ah, I see IEEE 1394 *does* use OUIs. Not at all surprising, of course.

So, the namespace should be used, not the appliation. In fact, given the
standard conversion from MAC-48 to EUI-64, we should probably just use one
namespace for both: my current ethernet card 00:50:FC:0C:63:69 would thus
be named "eui-64,00:50:fc:ff:ff:0c:63:69".

More than you ever wanted to know about this stuff: <URL:http://
standards.ieee.org/regauth/oui/>.

Of course, there *are* other namespaces.

MfG Kai
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