Yep. Only the first 64 bits matter. Almost every router out there is doing hardware forwarding in ASIC based on /64 and /128. In between /64 and /128 gets broken down into multiple /128's. That's what I've heard (and read) in a few places. Please correct me if I'm wrong.
For avoidance of confusion, if you're reading an IPv6 address as if it were a word written in the English language (that is, from left to right), the rightmost 64 bits are the ones that identify a host, and the leftmost are the routing information. :)
> Router's don't care much about the host stuff...
Sure. But, I was addressing mixmastamyk's assertion:
> I'm not a big fan of 128 bit addresses with ipv6, they are too long to read and write. Does anyone know why 64 bits was not good enough? [0]
If you're okay with writing and reading 64-bit hex strings, [1] the part that matters to most folks is the host identification part, which is 64 bits long. :)
