IP addresses are nothing but the four-number strings like 74.125.224.72 that one sometimes see in the browser’s address bar or in the smartphone’s system settings, or that one may have to type into the cable modem or WiFi router. For example, 74.125.224.72, is the address that should take you to Google. ARIN has now activated its “IPv4 Unmet Requests Policy.” Basically, it said that it was sorry, but if you want all of those requested addresses, you can take a smaller block or wait on ARIN’s waiting list until they somehow become free or buy them on the open market. Till recently, organizations in the ARIN region were able to get IPv4 addresses as needed. John Curran, president and chief executive of the Registry said “The problem is there are only those four numbers in addresses, which is why the system is called IPv4. It’s been in place for more than 30 years and even the architects of the Internet could not have predicted the amazing success and universal adoption of the Internet and World Wide Web.” Further, on Thursday, the nonprofit Asia Pacific Network Information Center reported that “Even optimistically, the total amount of unused or under-used IPv4 address space that could be made available only represents a ‘stop gap’ measure in the life of the IPv4 Internet. The demand for Internet addresses will only continue to grow.” In the early 1990s, the Internet Engineering Task Force (IETF) had anticipated an eventual depletion of IP addresses. Hence, to resolve the problem, they came up with a new version of the Internet Protocol. The old IP has version number 4; the new version is 6. IPv6 increases the length of IP addresses to no fewer than 128 bits, which is like increasing phone numbers from 10 to 40 digits. As a result, the number of available IPv6 addresses is, for all practical purposes, unlimited. For years, there is work going on what’s called IPv6 — longer addresses that also include letters. By using a more complex address, IPv6 increases the minimum amount. It has space for 340 undecillion addresses, or 340 followed by 36 zeroes – enough for each atom on Earth to be given one. Businesses must now move towards the new and spacious specification IPv6, if they have not switched yet. The companies will have to move towards hardware that’s compatible with IPv6, as moving could be expensive and time consuming. However, if they refuse to move over they might end up having to buy the limited and likely expensive IPv4 addresses that are left. The rest of the world moved over to IPv6 long ago. In 2011, Asia Pacific ran out of IPv4, while Europe, the Middle East and parts of central Asia in 2012, and Latin America last year. But North America that hosts many of the world’s biggest websites has finally run out of space. Since both IPv4 and IPv6 are meant to work side by side, one would ideally not see much impact from the switchover. But Internet service providers and large public organizations has been slow with the adoption. Google, which monitors whether you get to it through IPv4 or IPv6, says only 21 percent of its U.S. traffic comes through IPv6 and that’s the highest rate of any country in the world. “It is time for Internet service providers to move to IPv6 to enable the Internet’s continued growth,” Curran said. “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.” Or else, the Internet will remain rigid where it is today.