On Wed, Apr 21, 2010 at 9:35 PM, <valdis.kletni...@vt.edu> wrote: > On Thu, 22 Apr 2010 07:30:51 +0930, Mark Smith said: > >> " 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 >> >> Based on this analysis, the uniqueness of locally generated Global >> IDs is adequate for sites planning a small to moderate amount of >> inter-site communication using locally generated Global IDs." > > There is a measured rate by RIRs and the like on the order of 10^-6 for > accidentally issuing duplicate integers (roughly approximated by 2 cases of > duplicate ASNs out of (300K routes + 30K ASNs). In other words, unless you > have over 1,000 or so backdoor links, you're more likely to get screwed over > by > an administrative drone fscking up your paperwork than you are of a > statistical > collision.
it's not about the frequency of collision, it's about the cost to rectify one/two/some. and the complexity this adds to every host/router/device in/around the network (dns, firewalls, acls, etc... icky) -chris