The American Registry for Internet Numbers (ARIN), the organization which assigns IP addresses to devices connected to the internet, recently announced that it has run out of IPv4 addresses, one of the most common type of IP addresses (Internet Protocol Addresses), also known as numerical identifications for devices on the internet.

The shortage of IPv4 addresses will pressure internet service providers (ISPs), large organizations and software developers to migrate to IPv6, the most recent version of the internet protocol.

ARIN announced in a statement:

"The source entity (-ies within the ARIN Region (8.4)) will be ineligible to receive any further IPv4 address allocations or assignments from ARIN for a period of 12 months after a transfer approval, or until the exhaustion of ARIN's IPv4 space, whichever occurs first.

ARIN president and chief executive John Curran announced that there shouldn’t be an impact during the switchover from IPv4 to IPv6. According to Google Statistics, around 21 percent of U.S. traffic already comes through IPv6, registering the highest rate of any country in the world.

ARIN president and chief executive John Curran

However, the problem lies behind the compatibility between IPv4 and IPv6. Because the two internet protocols aren’t entirely compatible, the migration from IPv4 to IPv6 may prevent internet users from browsing through IPv5 web servers. According to Wired, internet service providers are currently working to provide a bridge or a compatibility layer in between these protocols.

"It is time for Internet service providers to move to IPv6 to enable the Internet's continued growth," announced Curran. "Businesses should be aware that this transition is already well underway for many service providers in the region and make sure that their public-facing websites are reachable via IPv6.”

As previously reported by Cointelegraph, the shortage of IP addresses came as a surprise to software developers and internet service providers, especially in the United States. However, ARIN and internet service providers still could offer IPv4 addresses that have been set aside for specific purposes. ISPs could also temporarily obtain lightly-used IP addresses, but it would not be enough to solve the problem due to the unprecedented growth of the world wide web in the past 20 years.

“Even the architects of the Internet could not have predicted the amazing success and universal adoption of the Internet and World Wide Web," said John Curran, president of the American Registry for Internet Numbers.

While IPv4 addresses are limited to around 4 billion addresses, IPv6, the new version of the internet protocol supported by all major operating systems is set to provide 340 undecillion addresses.