Since the early nineties, the Internet community has been concerned by the consumption of IPv4 addresses and several techniques have been proposed and deployed to reduce the consumption of IPv4 addresses. Network Address Translation (NAT) and Classless Interdomain Routing (CIDR) have been very successful. Unfortunately, the pool of IPv4 addresses is finite and we will run out of IPv4 addresses soon. An important milestone was reached today as the NRO announced that 90% of all IPv4 addresses have already been allocated.

The IETF has been discussing various techniques to deal with the lack of IPv4 addresses. Instead of trying to keep IPv4 alive by using ugly hacks such as carrier grade NATs or A+P addresses we should all start to move to IPv6. Unfortunately, while there was a huge growth of IPv6 allocations in 2008, this growth did not continue in 2009 and IPv6 only represents a very small fraction of the traffic on the global Internet.