This is not including the needed aggregation for multi-national registries, its fine for a single network but, still would tie your hands when sub-allocating to multiple LIR's. Regards Stephen Burley UUNET EMEA Hostmaster
Colleagues,
I've just done some calculations that shows the maximum theoritical utilisation that can be achieved is 75% whilst maintaining the minimum size of routing table. That is if you take a large number of subnets, each subnet containing a random number of hosts, and assign to each subnet the nearest power of 2 larger than the number of hosts, the utilisation you get is 75%.
This is a 75% utilisation per level of network hierarchy.
So if we assume 3 levels of network hierarchy and each level doing perfect routing aggregation and perfect address allocation we will get an overall utilisation of 0.75^3 = 0.422 == 42% overall utilisation for the TLA.
I'd like to bet that if we have a network with enough hosts to justify 64 bits of address space it'll also be large enough to require more than 3 levels of network hierarchy. Any requirements to get high address space utilisation out of IPv6 can simply be demonstrated to lack scaling qualities.
Regards,
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