[dns-operations] Embedding MAC address in DNS requests for selective filtering

[Robert Edmonds]

bert hubert wrote:
> If anyone thinks NSID is not a good way to do this, please also let us know.

I think this is not a good way to do this, at least because RFC 5001
says the client should not include any payload data:

   The resolver MUST NOT include any NSID payload data in the query
   message.

If you do end up doing this with an in-band EDNS option, I think it
would make more sense to use a new option code, and there are
approximately ~65.5K of them available for assignment or experimental
use :-)

I also think that naked MAC addresses should not be re-used as unique
device identifiers.  Instead, maybe consider some mechanism for
generating a stable, opaque identifier, maybe taking inspiration from
RFC 7217, which tries to get rid of the MAC addresses from traditional
IPv6 SLAAC addressing.

-- 
Robert Edmonds