North America has officially run dry of new IPv4 addresses

North America has officially run dry of new IPv4 addresses, the numbers that computers use to find each other on the internet.This means the region can allocate no more of the 32-bit network addresses to web hosting companies, cloud providers, organizations and individuals: they're all taken. The space is full, and it's being heralded as a key milestone in the internet's growth.

In the past few minutes, ARIN – the non-profit that oversees the allocation of IP addresses in North America – confirmed the available pool of the 32-bit network addresses is totally depleted. Last night, the team estimated there were just 1,024 IPv4 addresses left in its pool – dregs, in other words. Now that's all gone.

"The exhaustion of the free IPv4 pool was inevitable given the internet’s exponential growth,” ARIN boss John Curran said.The IPv4 space globally offers 4,294,967,296 network addresses – which seemed like an awful lot back in the 1970s when the internet was coming together. (Not all of those are usable on the public internet as some chunks are reserved. For example, the familiar 10.x.x.x and 192.168.x.x blocks are used for internal networks.)

IPv4 has been a loyal and faithful protocol since its inception, supporting 4.3bn internet addresses. But given the explosion in the number of internet-connected devices, that is not nearly enough.

According to one calculation, ARIN has about 134,000 addresses left.

Fortunately, a solution is at hand: IPv6, which has “ample availability”, ARIN says.

Existing IP addresses are a string of numbers such as 68.89.31.226, while an IPv6 address has eight four-digit hexadecimal numbers (where the numbers 10-15 are represented by the letters a-f). An example would be 2001:db48:1f70:54e3:9399:def8:7648:6ef8.

"While some companies, such as Google, have already switched to the new protocol, not all have done so."