The Internet is composed of millions of interconnected computers, each sharing a common addressing scheme, similar to addressing houses and businesses. The scheme, or protocol, used to communicate across the Internet is called, surprisingly enough, Internet Protocol (IP). Currently, the majority of organizations use IP version Four (IPv4), which is turning into a problem. IPv4 was first proposed in 1978 and can address a theoretical maximum of four billion machines. In an era when even your watch may soon want an IP address, we are quickly exhausting our current supply. To keep up with the demand for more devices, the Internet Protocol had to evolve.
The first papers describing the Internet Protocol were published in 1974. The authors, Vint Cerf and Bob Kahn, went on to develop Internet Protocol versions zero through three between 1977 and 1979. These first drafts were considered experimental, but the fourth version (version four) developed in partnership with DARPA and colleges around the world. It became the standard that the Internet is built on known as “IPv4”. IPv4 was developed in tandem with the Transmission Control Protocol. Together, they make up the TCP/IP suite. It didn’t take long until the first concerns about exhausting our global supply of IP addresses started in the 1980s.
The conversation on what to do about running out of IP addresses for the Internet has been ongoing since the 1980s. Since then many workarounds have been adopted. The most common workaround is to use only one public IP address which is reachable by anyone on the Internet for a single geographical location like your home or office. Using a single IP address, you can translate any group of agreed upon private IP addresses. In this way, a router becomes a gateway between the public Internet and your private home or office network.
Unfortunately, this fix will only last for so long. As more of the world comes online, and more devices become smart, the “Internet of Things” will consume ever more public IP addresses. To address this issue, the Internet Engineering Task Force developed the next generation scheme for addressing computers on the Internet, Internet Protocol version Six (IPv6).
Aside: It’s good not to get too hung up on version numbers in technology. The gap between IPv4 and IPv6 is explained by another experimental version, similar to versions zero through three, IPv5, which also known as Stream Protocol.
IPv6 has a much, much bigger addressable range than IPv4. In fact, as compared to IPv4’s four billion total addresses, adoption of IPv6 will limit every atom of every person on earth to eight billion addresses! It is assumed that mankind will never exhaust IPv6.
Unfortunately, adoption of IPv6 has been slow. The establishment of IPv4 across the globe has made the change process long and tedious. Concerns over compatibility, training, and security, as well as the lack of a significant motivating factor, have caused many organizations to postpone the transition to a later date.
In the very near future, however, the law of supply and demand will cause the downsides to IPv6 to be overshadowed by the cost of IPv4. While the longstanding Internet Protocol is not going away anytime soon, pure economics will push the adoption of IPv6, and a stable addressing platform for as far out as we can see.