7. Summary

Any address allocation and management policy for IP addresses used for Internet connectivity must take into account its impact on the scalability of the Public Internet routing system. Among all of the possible address allocation and management policies only the ones that yield a scalable routing system are feasible. All other policies are self-destructive in nature, as they lead to a collapse of the Internet routing system, and therefore to the fragmentation (partitioning) of the Public Internet.

Within the context of the current Public Internet, address allocation and management policies that assume unrestricted address ownership have an extremely negative impact on the scalability of the Internet routing system. Such policies are almost certain to exhaust the scalability of the Internet routing system well before we approach the exhaustion of the IPv4 address space and before we can make effective use of the IPv6 address space. Given the Internet's growth rate and current technology, the notion that everyone can own address space and receive Internet-wide routing services, despite where they connect to the Internet, is currently technically infeasible. Therefore, this document makes two recommendations. First, the "address lending" policy should be formally added to the set of address allocation policies in the Public Internet. Second, organizations that do not provide a sufficient degree of routing information aggregation to obtain access to the Internet routing services should be strongly encouraged to use this policy to gain access to the services.

Since the current IPv6 address allocation architecture is based on CIDR, recommendations presented in this document apply to IPv6 address allocation and management policies as well.