Phil Howard <phil@charon.milepost.com> writes:
IPv4 space is not enough for dedicating 1 IP address to every person.
Correction: IP space is not enough for dedicating 1 IP address with global scope permanently to every person. Remember: CIDR requires renumbering, which means that the permanence is no longer the case; this substantially added to the lifetime expectancy of IP. NAT translates at NAT borders which means addresses have local scope. This even more substantially adds to the lifetime expectancy of IP. NAT also mitigates the cost of renumbering to comply with CIDR. Note that with aa decent evolution towards describing services as a domain name and a service name that is relative to the domain name, then the IPv4 address space is essentially extended proportional to the number of autonomous NAT domains and within each such domain proportional to the number of useable ports to which the service names may map.
There are also increased costs involved in the processes being used to manage allocations of IPv4 space.
Allocations are local. ARIN/RIPE/APNIC allocate within one large NAT domain, and not within other NAT domains. As NAT continues being deployed, and in particular if very large scale NAT (e.g., between ISPs) becomes workable and efficient, then it is local registries and not ARIN/RIPE/APNIC that will be managing allocations of local IP addresses, and NATs managing translations at NAT domain borders.
With IPv4 space being managed better with CIDR, we do have more time to find the right way to deploy IPv6.
No, with IPv4 space being managed better with CIDR we have had time to develop and deploy NAT on a continually growing scale, and have had the time to reflect that this scales better than a migration to IPv6. What is not completely clear is that IPv4ever is the best approach, but what is completely clear is that NAT and the IPv6 work on protocol translation means that a better protocol than IPv6 can easily be deployed locally within a NAT/protocol translation domain.
Whether to IPv6 or not, maybe we should be looking at what next for BGP4.
A chainsaw right through it. Sean.