On (2010-07-25 10:28 -0400), valdis.kletni...@vt.edu and Mark Smith wrote similarly:
> > http://www.wolframalpha.com/input/?i=1-((2^40)!)%2F((2^40)^1000000+((2^40)-1000000)!)+ > > > > So if there are million assigned ULA's there is 36.5% chance of collision, > > if > > formula is right. > > Bzzt! Wrong, but thank you for playing. Point I was trying to convey is that you should not assume ULA to be globally unique. Visibility of IP can extend past routing, for example someone could use x-forwarded-for and assume rfc4193 to be as unique as any other IPv6 address. I personally have no beef with ULA and I don't mind that it can't be trusted to be globally unique identifier. It'll still allow well planned enterprise networks to avoid renumbering in M&A. -- ++ytti