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The Internet is running out of IPv4 gas

Or, to be more exact, the Internet running out of IPv4 addresses. Like it or lump it, we're all going to need to switch to IPv6.
Written by Steven Vaughan-Nichols, Senior Contributing Editor

If you listen to some people, businesses don't need to worry about the growing shortage of Internet IPv4 addresses. Instead, most "network owners find it more affordable to just make do with the [Internet] addressing scheme they're already using. This is so, so wrong.

When the Internet began, IPv4's possible 32-bit 4.3 billion addresses looked like more than enough. Things have changed.

We're running out of IPv4 addresses, the 32-bit numeric addresses that network devices need to connect to the Internet. All those mobile devices that we love so much like iPhones, tablets, and iPods are gobbling down IPv4 addresses like an elephant does peanuts. For the longest time, we managed to avoid running out of IPv4 addresses with the use of technologies like Network Address Translation (NAT) and Classless Inter-Domain Routing (CIDR), but those haven't been enough.

According to the Number Resource Organization (NRO), the group that oversees the allocation of all Internet number resources, announced in January 2010 that less than 10% of available IPv4 addresses remain unallocated. As Axel Pawlik, chairman of the NRO, said in a statement, "It is vital that the Internet community take considered and determined action to ensure the global adoption of IPv6. The limited IPv4 addresses will not allow us enough resources to achieve the ambitions we all hold for global Internet access."

You don't have to believe Pawlik though. You can watch the IPv4 addresses go down the virtual drain for yourself at the IPv4 Address Report. When I last checked it, on September 8th, we were down to 5% left of all IPv4 addresses.

Administratively, here's how it works. Internet IP addresses are allocated by the Internet Assigned Numbers Authority (IANA), which in turn is run by the Internet Corporation for Assigned Names and Numbers (ICANN). IANA distributes IP addresses to regional Internet registry (RIRs) who issue these addresses to ISPs and from the ISPs to you.

What's going to happen next, at the current rate, is that IANA will run out of numbers to give the RIRs on May 26th 2011. After that, the RIRs will give some lucky user the last IPv4 Internet address on or about January 25th 2012.

Then, things get interesting. If you're smart and your IT department is well-funded, you'll have switched to IPv6 by then. Human nature being what it is I don't expect that to happen.

Instead, we'll see a confusing mess of Internet address markets. These will probably look something like the one that now exists for valuable domain names, but I'll talk more about that, and what's involved in switching over to IPv6 in future blogs. Eventually, you see, we will all have to switch over to IPv6, but the process will take years and it isn't going to be easy, simple, or pretty.

Brace yourself network administrators, CTOs, and CIOs, we're in for a heck of a ride.

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