On Mon, 19 Jul 2021 09:27:13 -0700, Nathan Angelacos wrote:
On Mon, 2021-07-19 at 08:51 -0700, Randy Bush wrote:
Well, for SLAAC you need a /64
this is not true
randy
That is cool! Can you point me to the correct RFC please?
from the war zone, draft-classless6/draft-nbourbaki-6man-classless-ipv6 said The length of the Interface Identifier in Stateless Address Autoconfiguration [RFC4862] is a parameter; its length SHOULD be sufficient for effective randomization for privacy reasons. For example, 48 bits might be sufficient. But operationally we recommend, barring strong considerations to the contrary, using 64-bits for SLAAC in order not to discover bugs where 64 was hard- coded, and to favor portability of devices and operating systems. Note that OpenBSD ships with SLAAC for lengths longer than /64. Nonetheless, there is no reason in theory why an IPv6 node should not operate with different interface identifier lengths on different physical interfaces. Thus, a correct implementation of SLAAC must in fact allow for any prefix length, with the value being a parameter per interface. For instance, the Interface Identifier length in the recommended (see [RFC8064]) algorithm for selecting stable interface identifiers [RFC7217] is a parameter, rather than a hard-coded value.