We started with fec0::/10 for site-local addresses — but that is now deprecated. Instead, we now have fc00::/7 reserved, with fd00::/8 dedicated to /48 nets for Unique Local Addresses.
What's the best practice for picking the least-sig 40 bits to give you an org-level /48?
…is everyone using the SIXXS voluntary registry? (seems dubious to me)
…just use RFC4193's guidance for picking (via it's algo)?
…anyone have an online implementation of that algo?
Picking our 40 bits doesn't seem hard; I'm just trying to pick them the "right" way, if I can.
Best Answer
Its always best to stick to the relevant RFC when possible. In this case, your two options aren't mutually exclusive. SIXXS' generator should actually generate you a prefix based on RFC4193's algorithm.
So you would just generate your prefix using SIXXS' tool (or another one you find), and if you feel like it, register it with SIXXS.