* Saku Ytti > Yes, SLAAC, 4862 clearly does not forbid it, and there is no > technical reason. But as you state, 2464 does not specify other > behaviour. Writing new draft which specifies behaviour for arbitrary > size wouldn't be a challenge, marketing it might be. FYI: RFC 7421 is an in-depth discussion of the fixed 64-bit boundary. Tore