On Thu, Feb 23, 2017 at 5:20 AM, Brian E Carpenter <brian.e.carpenter@xxxxxxxxx> wrote:
Nobody is saying that /64 isn't extremely widely used where it's
appropriate to have a portable fixed length IID. Set the default
at 64 and trust operators to change it where they need to.
That's realistic.
As a host developer I strongly oppose that. It will make life easier for network operators but make life harder for host OS developers, host operators, and host users.
And it is absolutely inappropriate to change this now in given that the /64 boundary has been the standard for the last 20 years. It will break deployed code that relies on the current standard. (That includes concrete code I can point to that I know runs on tens of millions of devices.) That's not acceptable to do in a standard reclassification.