IPv6: The Next Generation
CECS5400
Roy A. Zumwalt
December 11, 1999
Those in the field are bombarded by them daily, those who aren’t are frustrated by them. We all knowingly shake our head when they are used and pretend that the world is in its orbit and there is nothing new under the sun. But they persist and even thrive. They grow more numerous every day. Ever more numerous, ever more perplexing and ever more a vital part of the way we communicate. They are technical acronyms. While this acronym phenomenon itself would provide enough material to write volumes on, I would like to focus on one. This one, whether you are an IT professional (see, I told you they are everywhere) or a layperson, you have heard of. It is inseparable from the web, the net, electronic mail and telecommunications. It is IP or the Internet Protocol. It is the second half of the TCP/IP that is the standard for data packet transmission over the web. TCP, or Transmission Control Protocol, is actually a separate protocol from IP, even though the two are usually referred to as the same thing. TCP/IP is also actually an entire collection of protocols called a protocol suite. The suite includes application protocols for sending e-mail, transferring files and doing terminal emulation[1].
IP has been around for a while. ARPANET (Advanced Research Projects Agency Net) had put together the first "network" of computers and wanted a way for them to be able to communicate with each other, even if one or several of the links connecting them were broken. It had only a couple hundred computers attached to it but it was beginning to grow. As more institutions wanted an easier way to share information they joined this small but existing network. This caused ARPANET to split into ARPANET and MILNET. At first, these were independent networks but very soon after there came the need for them to be connected. So DARPA (Defense Advanced Research Projects Agency) funded the development of TCP/IP so that the two networks could talk to each other[2]. The protocols worked so well that they would allow several thousand networks to communicate with each other. TCP/IP was so successful at this that it is still around today.
The protocols, however did not gain wide spread use until the University of California at Berkley developed a little operating system called UNIX and decided to bundle TCP/IP with their software distribution kit. Universities (in particular) across America began getting connected at a phenomenal rate. Then in 1980, the Secretary of Defense mandated that all computers connected to the ARPANET use TCP/IP. That basically sealed the fate of TCP/IP. It had made it to the big time as a standard for (multiple) network communications.
IP has now stood the test of time. While we are currently on version 4 of the protocol, it has now been in widespread use for about 20 years. That is practically a lifetime when measured on the scale of the technology revolution. But it is (the current version) becoming dated. It still works perfectly and many experts suggest that it will take another 20 years to be phased out (something I disagree with), but it needs to be updated. There is one overpowering reason this is so. It is running out of addresses. You see TCP/IP (version 4) is only a 32-bit protocol. What that basically means is that the number of addresses that can be created with those bits can only be so large. In the current version there is an upward limit of about 4 billion addresses. And so it is being updated to IP version 6, or the new version is alternatively called IPng or IP next generation.
The new version has kept all of the things that made IPv4 so useful but has also added many new features. It will allow for a significantly larger number of addresses, it has added security features, and it has become more “intelligent” in that it will autoconfigure itself in several different ways. It will also provide many special addresses that can be used in certain ways to test systems, lower traffic on the web and broadcast important packets to multiple addresses.
As stated the first great benefit to come out of IPv6 will be the number of addresses that it provides. 4 billion was the limit on IPv4 and there is a limit associated with IPng, but I couldn’t tell you what that number is. I can write it out but I couldn’t say it, it is that large. The limit on addresses in Ipv6 is 340,282,366,920,938,463,463,374,607,431,768,211,456. The reason that the address space can be this large is because IPv6 is 128 bits long instead of 32. It has been conservatively estimated that this provides about 1,564 addresses per square meter of the earth. The conservatism is based on wasted IP space due to inefficiencies in allocation of these addresses. The actual number of addresses it provides per square meter of the earth is approximately 665,570,793,348,866,943,898,599.[3] While I’m not sure what the benefit of having this much address space available, I do think this is one of those instances where we don’t know what we don’t know, so there may be a legitimate need for this excessiveness. For instance I can see a possible need for multiple addresses for the same “node” or computer depending on what the particular function of that computer is for a particular packet.
The next great improvement in IPv6 is the added security it offers. Electronic commerce or e-commerce is the latest buzzword to come along in the merging of the net with corporate America. With it comes the increased need for transactions that are executed over a network to be secure. Packet authentication, data integrity, and confidentiality are a must if businesses are going to allow and encourage customers to engage in commerce over the web. The authentication process guarantees that the packets are coming from the indicated sender, the integrity insures that there have been no changes made to the packet while it was in transit and the confidentiality just insures that no one has “peeked” into the contents of the packets as they were being transmitted. All of these added features to IPv6 will have a significant impact on education, commerce, and even entertainment. For instance, it may be possible soon to attend class, reconcile your bank statement, purchase groceries and order a movie on demand all from your living room with the visual interface being handled by your television set. And people thought we were isolationists before!
Once IPv6 is fully integrated into the existing and proposed infrastructure, we will have the ability to experience a much higher quality of multimedia. Audio and video streaming will approach “real time” and offer mediums for communications that we have only dreamed of up until now. For instance, let’s add to the scenario listed above. Lets add to the class/banking/entertainment scene a phone call placed to a friend in another state. You still may not have to get off the couch, and you will be able to see exactly what your friend is doing at that very moment once they answer the “phone”. You may both have cameras that pick up the activity in your homes and send it real time to the other. This is something I know I have been waiting for since I was a child. It to me will be like staring in a movie every time I make a phone call. I just hope nobody calls me too early in the morning. I’m a little grumpy until after my first 7 or 8 cups of coffee.
One last addition to IPv6 that is noteworthy is the ability for it to configure itself automatically. It can do this in any of several ways. The first way is called autodiscovery. This allows computers and other hardware components to automatically discover who its neighbors are, what network it is on and what type of internal transactions are allowed on that network. The second way it can configure itself is called, you guessed it, autoconfiguration. This automatically assigns an IP address to a network interface card. The last way is called autoregistration which allow computers (mostly servers) to automatically register an address with DNS or Domain Name System, the database responsible for keeping internet addresses straight.
It is also important to note that IPv6 is backward compatible with IPv4. There will not be a single moment in time where all of the implementations of IPv4 will be upgraded to IPv6. It will happen rather slowly over time. IPv6 will be able to resolve addresses that are in 32 bit form, however IPv4 will not be able to resolve 128 bit addresses. What this means is that while it doesn’t all have to be done at once, there will have to be some thought put into how to bring it all together. It will have to be a top down implementation. Routers, switches and servers will have to be brought up to version 6 before the computer clients themselves can take advantage of version 6.
There is a test group out there already making IPv6 a reality. The group is called 6Bone. I believe the name is comes in part from the version number of the protocol and from the word backbone, used to refer to the base infrastructure of the web. The group currently has participants from 42 countries and most implementations have been very successful (see below for an image of the U.S. IPv6 test sites and their connectivity). I think what that actually means is that the rollout of IPng has begun. Though it will take several years, the growth of the internet will push universities and industry to adopt the new standard. Not only so, but the demand for better, faster, more reliable communication, worldwide, will drive the implementation.
The importance of IP cannot be stressed enough. It basically is the reason the web and internet exist today. The impact that it has had and will continue to have on society is nothing less than incredible. The ease with which IP can move information around the world has truly been one of the most important steps in making the earth a “global neighborhood”. We no longer view time, distance, space, relationships or information in the same way that we did 10 years ago. It is literally granting the individual and the collective masses the ability to communicate at a new level. This can be good and bad. For instance, you may now be best friends with someone you have never met face to face. You may be more open to their culture, their personality, and their lifestyle than you would be if you “hung out” with them in person. These things are good but if these types of relationships are at the expense of other interactive face-to-face relationships, it could be very bad. This is of course a personal opinion and the verdict is still out on the long-term affect of cyber-relationships.
One other area that IP will continue to have a huge impact is in education. Universities in particular, tend to be on the cutting edge of technology. The very environment itself invites discovery, invention, research, exploration and experimentation. Because of this it is very likely that you will first see full scale implementations of IPng in an educational environment. This may mean that students will be the first to benefit from the new standards. They may be able to really attend classes from a remote location and collaborate on projects without ever physically meeting their project partners. IP will continue to be a world wide standard for Internet communications. That is at least for the next 20 years or so.
There is less material on IPv6 than I thought there would be. Most of it can be found as a subsection of IP documents or as a separate chapter in a book on IPv4. I did manage to find about 6 titles that seemed to be dedicated to Ipv6 and listed a couple of the more interesting ones in the bibliography. There were some web sites to be found on IPv6. The most informative one is http://playground.sun.com/pub/ipng/html/INET-IPng-paper.html. This site is probably the most easy to find. It will usually turn up under any search engine and is very often referred to from other IPng sites. A good place to get general information about the Internet as a whole and the latest breaking news about IPv6 is http://www.stardust.com/ipv6/news.htm. Another site that is completely dedicated to the new Internet protocol is http://www.ipv6.org/. Http://www.6ren.net is a sponsored by The Energy Sciences Network and covers the implementation issues associated with Ipv6. If you are interested becoming a player in the IPv6 arena immediately, you need to visit http://www.6bone.net/.