Hi Jari, On 11-09-19 02:35 AM, Jari Arkko wrote: > Following up with a personal comment. > > The draft allocates an interface ID and an EUI-64 MAC identifier from the IANA block. These are two separate, unrelated allocations. > > The main criticism in RFC 5453 for making additional interface ID allocations is that old implementations do not know about them and may collide when making an allocation. I'm wondering if it would be better to allocate an interface ID that is based on the allocated EUI-64 identifier per RFC 2464? Then we would at least use the same format as other interface IDs and a collision would likely mean inappropriate use of the IANA EUI-64 identifiers. Note that privacy and cryptographic addresses set the u/l bit to zero, whereas EUI-64 interface IDs usually have it at one. Sri's draft is silent on what kind of number should be allocated for the interface ID, perhaps some guidance here would be useful. This sounds like a great idea. I am not sure that IANA has a reserved EUI-64 block like you suggested, but they certainly have a ethernet address block (MAC-48). We can instruct the IANA to assign a MAC address that maps straight into the IID. e.g. 00-00-5E-00-03-00 and the IID 0200:5eff:fe00:0300 Thanks Suresh _______________________________________________ Ietf mailing list Ietf@xxxxxxxx https://www.ietf.org/mailman/listinfo/ietf