While most Western countries and China are making efforts to become IPv6 ready, the number of available IPv4 addresses is dropping rapidly, and China is the first one to be hit by the lack of assigned addresses. It is expected that about 828 days from today (January 1, 2011), China will have no more IPv4 addresses to allocate.

Educational and research institutions have been the first to be migrated to the IPv6 networks, which are able to hold 40,282,366,920,938,463,463,374,607,431,768,211,456 IP addresses (2 to the power of 128.)

The IANA global pool holds 654 million addresses and another 325 million held by five different Internet Registries in different parts of the world. With an average of 1 million new IP addresses allocated each day, the IPv4 supply will last for nearly 3 more years.

The United States has 1.44 billion IP addresses followed by China which has nearly 167 million addresses.