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Re: [STDS-802-Privacy] Locally-administered bit and OUI registration


You should have a look at this IEEE RA tutorial:

It explains that the IEEE RA assigns OUIs with the local (U/L) bit set to 0 and that it assigns CIDs with the local bit set to 1. If you flip the U/L bit in an OUI, you don't have an OUI; what you have is an invalid CID or someone else's CID.

The P802c draft (D1.2), currently under development, says:

"Changing the X bit of an RA-assigned OUI is not authorized by the IEEE RA, does not result in a valid CID, may invalidly duplicate a valid CID assignment, and shall not be used as the basis of an ELI." In P802c, the ELI ("extended local identifier") is used as a local MAC address.


Roger B. Marks <r.b.marks@xxxxxxxx>
EthAirNet Associates

> On 2016Sep 20, at 7:46:43AM, Matte Célestin <celestin.matte@xxxxxxxxxxxx> wrote:
> Hi all,
> I'm currently working on studying the adoption of MAC address
> randomization over time.
> As you know, vendors have to register a OUI (also called MA-L) at IEEE
> before using it to generate MAC addresses for its devices [1].
> Some (but not all) devices set the locally administered (LA) bit of the
> OUI part of their MAC address to 1 when using a random MAC address.
> I'm wondering if the newly-created OUI has to be registered as well to
> be used; I can't seem to find any text stating if this has to be done or
> not, or if this is done implicitly.
> In the whole oui.txt file (listing all registered OUIs), a little bit
> more than a dozen OUI withs the LA bit set to one are listed, and do not
> correspond to devices actually seen in the wild doing MAC address
> randomization.
> So, my questions are:
> - are there any texts specifying whether OUI with LA bit set to 1 have
> to be registered to be used?
> - are there any texts stating that OUI with LA bit set to 1 is
> automatically reserved for the vendor when the correspond OUI with LA
> bit set to 0 is registered?
> [1] :
> Regards,
> -- 
> Célestin Matte