On Wed, 18 Jul 2012 21:07:35 +0300, Saku Ytti said:
If collision occurs, if dispute occurs, provability that one party did not use BCP method can be useful to solve dispute and decide who renumbers.
Looking at actual numbers out of RFC4193: The following table shows the probability of a collision for a range of connections using a 40-bit Global ID field. Connections Probability of Collision 2 1.81*10^-12 10 4.54*10^-11 100 4.54*10^-09 1000 4.54*10^-07 10000 4.54*10^-05 OK? So even if you merge and re-merge, and go on a massive buying spree and accumulate a network where you have to interoperate 1,000 ULAs, you're *still* looking at a literally million-to-one shot. And if you only have a mess of 100 ULAs, it's a billion-to-one. Now, compare that to the chances that you'll acquire 2 companies, both of whom had an employee who didn't actually generate a proper random number, but did this sort of thing instead: http://www.spinics.net/lists/linux-driver-devel/msg26431.html A lot of people are worrying about the wrong problem.