Vint Cerf takes rap for running out of IP addresses

A father of the Internet, Vint Cerf says he never anticipated the world would need more than 4 billion IP addresses.

Lance Whitney Contributing Writer
Lance Whitney is a freelance technology writer and trainer and a former IT professional. He's written for Time, CNET, PCMag, and several other publications. He's the author of two tech books--one on Windows and another on LinkedIn.
Lance Whitney
2 min read

Who knew that 4.3 billion Internet addresses wouldn't be enough?

Vint Cerf
Vint Cerf Google

Internet pioneer Vint Cerf has sounded the alarm bell once again by warning that the world is about to run out of IP addresses. Cerf, who also serves as Google's chief internet evangelist, pinned the blame on himself for the lack of sufficient addresses in a recent interview published in the Sydney Morning Herald.

Initially seeing the Internet as just an experiment that would eventually end, Cerf said he never anticipated the world would need more than the 4.3 billion addresses currently capable of being allocated.

"Who the hell knew how much address space we needed?" Cerf said in an interview with journalists in Sydney, Australia.

Of course, Cerf is certainly being hard on himself. No one could have foreseen the huge number of mobile devices, consumer appliances, and array of Internet-connected gadgets that would require their own unique addresses.

Cerf, known as a father of the Internet, also cautioned that the current crop of 4.3 billion addresses is due to run out within a few weeks. But when Cerf points to those addresses, he's specifically talking about ones that use the current IPv4, a protocol that limits an IP address to four 8-bit numbers, or 32 bits in total, thus allowing for around 4.3 billion possible combinations.

The world has known for years that we would eventually run out of IPv4 addresses, so industry has been busy striving to make the transition to IPv6. The new protocol, which uses four 32-bit numbers, or 128 bits in total, would allow for 340,282,366,920,938,463,463,374,607,431,768,211,456 unique addresses, hopefully enough to last the world for quite awhile.

Among those working on the jump to IPv6 is Google itself. A recent blog post from the search giant discussed the coming of World IPv6 Day. Set as the first real test flight for IPv6, that day will see Google, Facebook, Yahoo, and a host of Web sites and Internet providers offer their content and services through the new protocol. The goal will be to see what works and what doesn't and determine what kinks need to be ironed out.

Though Google says the vast majority of Internet users should be unaffected by IPv6 day, some may run into connection problems depending on how their devices are configured. The World IPv6 Day Web site offers a test that people can run to see if their own PCs and their Internet providers are set up to handle the new protocol.