Remember how, a decade ago, we told you that the Internet was running out of IPv4 addresses? Well, it took a while, but that day is here now: Asia, Europe, and Latin America have been parceling out scraps for a year or more, and now the ARIN wait list is here for the US, Canada, and numerous North Atlantic and Caribbean islands. Only organizations in Africa can still get IPv4 addresses as needed. The good news is that IPv6 seems to be picking up the slack.

ARIN, the American Registry for Internet Numbers, has now activated its “IPv4 Unmet Requests Policy.” Until now, organizations in the ARIN region were able to get IPv4 addresses as needed, but yesterday, ARIN was no longer in the position to fulfill qualifying requests. As a result, ISPs that come to ARIN for IPv4 address space have three choices: they can take a smaller block (ARIN currently still has a limited supply of blocks of 512 and 256 addresses), they can go on the wait list in the hopes that a block of the desired size will become available at some point in the future, or they can transfer buy addresses from an organization that has more than it needs.

“If you take a smaller block, you can’t come back for more address space for 90 days,” John Curran, CEO of ARIN, told Ars. “We currently have nearly 500 small blocks remaining, but we handle 300 to 400 requests per month, [so] those remaining small blocks are going to last between two and four weeks.”