
Not long after the Internet and World Wide Web were unleashed on the public, plans were already underway to increase the potential pool of IP addresses available for allocation. The version of the IP protocol standard most in use today, IPv4, was released way back in 1981 and deployed in 1982. This version is a 32-bit protocol with 2^32 possible addresses. That’s over four billion possible IP addresses. Back in the early 1980s, that seemed like more than we’d ever need, but by 1998 the Internet Engineering Task Force (IETF) had formalized a successor protocol known as IPv6 to deal with the anticipated exhaustion of IPv4 addresses.IPv6 uses a 128-bit address which works out to an insanely large number of possible addresses: 340 undecillion addresses to be exact. That looks like a made up word. The need for such a vast number of addresses is a result of the explosion of all sorts of internet-connected devices. These days, everything from webcams to DVRs to baby monitors and of course all those smartphones out there can request an IP address and connect to the internet. Many of these devices make up what has become known as the “Internet of Things” or IoT. Probably not too many engineers back in 1981 anticipated a dryer or refrigerator being able to connect to the internet. Fast forward 35 years and we’ve officially run out of IP addresses with the last blocks of IPv4 addresses having been allocated.In the meantime, we’ve been able to greatly expand the number of connected devices beyond the capabilities of IPv4 by employing several Band-Aid solutions with the primary one being Network Address Translation (NAT). NAT allows multiple devices behind a router to use private IP addresses that are not seen beyond the private network. Only a single public IP address is required to support such a network. This solution has worked great, but it has its limitations. The main one being that it’s not possible to directly address devices attached to the private network, thus limiting the full potential of IoT.Unlike many technology standards, IPv6 is not backwardly compatible with IPv4. Routers built with either standard are unable to route traffic to networks using the other protocol. We again, have Band-Aid solutions coming to our rescue. IPv6 has the capability of running a “dual stack” that allows conversion between IPv4 and IPv6 and in effect, the existence of parallel networks. There is also IPv6 tunneling which allows the routing IPv6 traffic over an IPv4 network. The reality is that about 90% of networks are still running IPv4 despite the capability of most clients, including contemporary Mac and Windows machines, to run IPv6. It’s the ISPs that have been slow to migrate to IPv6. It’s almost hard to blame them for the cost of chucking out perfectly good routers in order to offer IPv6 to their customers' networks is almost not worth it.So, what are the benefits of switching to IPv6?As previously mentioned regarding NAT, every device will be accessible on the public network (internet) with IPv6. This will make things easier for implementing home automation, file sharing, online gaming and peer-to-peer applications. In terms of security, IPv6 offers both distinct advantages over IPv4 as well as several unknowns. The use of encryption and techniques for preventing packet spoofing make IPv6 more robust in terms of data integrity and authenticity. IPv6 also does a better job of assuring that packets get to their correct destination without being intercepted. Overall, IPv6 has the advantage of being built with security in mind, something that wasn’t much of a concern in the "more innocent" days when IPv4 was released. On the flip side, IPv6 hasn't been fully targeted and tested by the bad guys, so chances are good that there are vulnerabilities lurking within it that have yet to be discovered.When it comes to performance things are not so clear-cut. IPv6 speeds up data with more efficient packet handling techniques such as not needing to check packet integrity. Address conflicts typical under IPv4 are eliminated with IPv6 due to the enormous pool of available IP addresses it supports. However, some contend that the increased complexity of IPv6 routers, in fact, slows things down.
Independent testing has shown IPv4 to outperform IPv6 in certain cases. Fell free to
test your own network and ISP.Regardless of any performance debates, the primary issue of having run out of IP addresses with IPv4 remains and the switch over to IPv6 is inevitable. In fact, it’s already begun. A test of IPv6 was conducted worldwide back in 2011 and was dubbed “IPv6 Day.” It was discovered that most devices handled the switch over quite well. What was eye-opening, though not too surprising was that most of the traffic run that day ended up being IPv4. The official switch over to IPv6 occurred a year later in 2012, though the majority of the traffic was and still is IPv4.What should you do to get ready for the continued transition to IPv6? As an end user, not much. Most IP devices now ship with IPv6 capability built-in. IT professionals and Cybrarians, in particular, will want to get up to speed quickly with the details of the IPv6 protocol (the addressing scheme is quite different from IPv4). There will, of course, be the inevitable security concerns surrounding a full rollout of IPv6 and they will evolve over time. And forever running out of IP addresses with the full switch over to IPv6, perhaps we shouldn’t get too complacent as folks did back in 1981. Consider sci-fi scenarios such as the emergence of nanobots and the mass colonization of other planets with their own universe of devices needed to connect to the “universe wide web.”