>> but i am having a hard time reconciling 2.4.4's insistence on a >> mandatory 64-bit uuid in all unicast global addresses with 2.4.0, rfc >> 6141, widespread operational practice, ... clue bat please. > > This was discussed extensively in 6MAN and resulted in RFC7421 > "Analysis of the 64-bit Boundary in IPv6 Addressing”. The text in > rfc4291bis is: > > For all unicast addresses, except those that start with the binary > value 000, Interface IDs are required to be 64 bits long. > Background on the 64 bit boundary in IPv6 addresses can be found in > [RFC7421]. thanks for the review that the wg came to this decision in conflict with operational practice and its own statement in 2.4.0. i did read the documents. since it is incorrect, ietf last call seems to be the time to fix it. to be clear, i have no problem with iids being 64-bit. my issue is with unicast globals being classful in 2.4.4. randy