A new Internet is coming—whether you like it or not!

The brave new world of IPv6 - Image by David Farley

“Look out! The world is about to run out of network addresses.”

Business network users have been hearing this warning for some time. Is this a real concern, or is it simply a case of “the boy who cried wolf?”

The current Internet addressing scheme, commonly known as Internet Protocol version 4 or IPv4, was invented in the late 1970s. It provided 4,294,967,296 or approximately 4.3 billion Internet addresses. In 1975 the earth’s entire population was about 4 billion. To IPv4’s designers that meant just about one Internet address per person. Certainly that should have been plenty—especially, since, at the time, only a handful of developed countries had Internet access. It was totally unimaginable that the IPv4 address space could ever be exhausted.

What was not anticipated was that the IPv4 protocol would be required to do the plethora of things that it is being used for today. It also wasn’t anticipated that there would be a need for multiple network addresses per person. But such has proven to be the case.

Many of us use more than one network address. For example, suppose that you have a desktop PC at work, you also have a notebook at work and you have a business Smartphone with Internet access. That’s three addresses. You get home and you have a personal laptop and your personal Smartphone. That’s two more addresses. Now you, one human being, have claimed five Internet addresses. Multiply that by the current world population estimated to be approaching 7 billion and you get 35 billion network addresses—nearly ten times more addresses than IPv4 supports.

Now, just to be accurate, the population of the world typically doesn’t have five Internet attached devices per person. A large percentage of the Earth’s population, especially in underdeveloped countries, has no Internet access at all. (Although happily this is rapidly changing.) In addition, there are other mitigating factors like Network Address Translation (NAT) where one IP address can represent up to 255 individual addresses. A protocol called Dynamic Host Configuration Protocol (DHCP) also has helped by, in effect, loaning out addresses for hours or days and then reclaiming those addresses. All of this has given IPv4 an extended life.

Still, we can’t keep this kind of growth up forever and stay within IPv4's address capability. Therefore, we now have the appearance of a new address protocol called IP version 6, or IPv6. (Don’t ask what happened to version 5. We seem to have jumped right over it.)

The address IPv6 space is four times larger than an address in IPv4. It allows for (big breath now) 340,282,366,920,938,463,463,374,607,431,768,211,456 (3.4 x 10^38) possible addresses. In case your head spins looking at all those commas, that’s 340 trillion, trillion, trillion addresses. It’s pretty hard to fathom just how big that number really is. The point is that IPv6 addresses the Internet numbering needs of the earth’s citizens and their network devices for some time to come.

IPv6 adoption has been rather slow (the protocol was created way back in the early 1990s,) but never the less it is finally happening. Some countries have already adopted it. While the United States has been slow to embrace IPv6, this is beginning to change now that the Federal government has mandated its use in government agency networks. So if you haven’t heard your company IT people talk about converting your network to IPv6, I expect that you will shortly. The world is changing in more ways than one.