IPv4 vs. IPv6 By Melanie McCormick Web Research Term Paper October 7, 2008 OMGT 5823: Computer Applications Instructor: Marita Ellixson and Nancy Sloan Introduction Improving a networks availability is the process of improving an existing network for better performance and reliability. Network improvement has become crucial to our pursuit of life and happiness in this modern generation. However, police departments, hospitals, businesses, individuals and virtually anything we depend on runs on their networked computer systems.
The more we depend on these networked computer systems, the more it affects us when they stop working to our satisfaction. Those of us that are involved in the planning, designing, building and operation of these networks, must also be able to predict problems in advance and also allowing rooms for scalability. Predicting problems in advance allows us to reduce the impact of these problems. With predictions of improved network availability, we can make sure our networks are going to service people satisfactorily before we build them.
However, users of networks are expecting more from networks when compared to the early days when a network was meant for e-mail and resources sharing e. g. printers, files etc. Today, businesses depends mostly on networks for the purpose of transacting their business such as video conferencing with partners abroad, web-based order entry, payment processing and customer relationship management, to name a few.
When these mission critical services are unavailable or performing poorly, they can bring business activities to a halt, affecting end user productivity, revenue, and customer satisfaction – hence, network availability should not go down but improved. Internet Protocol The Internet Protocol (IP) is the most widely-used method for transporting data within and between communications networks. It is as useful for the growing field of intranets (networks internal to an enterprise or organization and not connected to the outside world–e. g. a network used for classified processing) as it is for the geographically distributed, highly heterogeneous Internet. IP combines the functions of internodes linking with those of links between physical networks to provide communications paths between nodes on different networks. IP is called connectionless because it resembles the Postal Service or Western Union more than it does the telephone system. When a node using IP wishes to send a message to another such node, it simply sends the packet, properly addressed, analogous to mailing a letter or sending a telegram. In fact, another name for an IP packet is a datagram. ) The telephone system, on the other hand, creates a connection between two users which is maintained for the duration of the information exchange. Unlike the Postal Service, however, the services of IP can be used to create a connection-oriented operation mode, but this is the job of higher-level protocols and applications (such as TCP, File Transfer Protocol [FTP], Telnet, and others). In IP’s connectionless design, every packet is treated completely independently from all others. The IP Packet IP centers around the concept of a packet.
A packet is also known as a datagram, although that term is also used in the context of a number of different protocols at different levels of communications architecture; the term datagram specifically implies that the protocol operates in connectionless mode, as described above. Pursuing the Postal Service analogy used previously, an IP packet is comparable to a letter, although it is different in some important ways. An IP datagram consists of a header and a payload. The header is analogous to the envelope handled by the Postal Service, while the payload is analogous to the contents of that envelope.
Note that the post office is not permitted to open envelopes or peek inside; its entire job can be done by looking only at the outside of the envelope. Similarly, IP can do its job based on the contents of the header alone (ordinarily, that is, with some exceptions for special handling cases, just as the post office may open envelopes to check for contraband or for information when an envelope is undeliverable as addressed and provided with no return address, causing it to end up at the dead letter office).
There are a number of other fields in the IP packet header, especially in the more complex IPv4 header, but their purpose is either superseded in IPv6 or else is too technically detailed. I summarize the important points of the IP header in the following list: Version number Size Source and destination addresses Counter controlling lifetime of packet Service type Etc. (a group of less-important components) IPv4 vs IPv6 Background, Definition, and History Internet Protocol next generation (IPng) which has better security and increases Internet addresses from four to 16 bytes, to cope with the explosive growth of the Internet is born.
This is a version of Internet Protocol reviewed by the Internet Engineering Task Force (IETF) standard committees to replaces Internet Protocol version 4 – sometimes referred to as IPv4 while the official name of IPng is IPv6 (Internet Protocol version 6). IPv4: Short for Internet Protocol Version 4 was the first version of the Internet Protocol to be widely deployed, and forms the basis for most of the current Internet. Most of today’s internet uses Ipv4 which is almost 20 years old. There has been one major problem with Ipv4, it is running out of IP addresses (IP addresses are a unique identifier for a computer on the internet).
It uses 32-bit addresses, which is limiting to 4,294,967,296 unique addresses, many of which are reserved for special purposes such as local networks or multicast addresses, reducing the number of addresses that can be allocated as public Internet addresses. However, as the number of IP addresses available is consumed, an IPv4 address shortage appears to be inevitable in the long run. For the purpose of improving network availability, the limitation of IP address Ipv4 has helped stimulate the push towards IPv6, which is currently in the early stages of deployment and will eventually replace Ipv4. IPv6: Short for Internet Protocol Version 6 is nitially called IP Next Generation (IPng). It is designated as the new version for the IP standard. IPv6 is intended to replace the previous standard, IPv4, which only supports up to about 4 billion (4 ? 109) addresses, whereas IPv6 supports up to about 3. 4 ? 1038 (3. 4 dodecillion) addresses. It is expected that IPv4 will be supported until at least 2025. This is to allow time for bugs and system errors to be corrected. There were several reasons for the development of a new standard in the face of a current working and widely used system. Most important was the exhaustion of the 32-bit address space of IPv4 which is stated above.
Although 32 bits provides a possible 4 billion addresses or so, the existence of reserved address ranges, structure of network addresses within those 32 bits, and other considerations led to a forecasted crisis in address availability for the early 2000s, if not the late 1990s. There were other problems of a more technical nature whose impact would fall primarily on performance, without creating the problem of total inaccessibility for those who needed new addresses, but which needed to be dealt with very soon if the Internet was to continue to expand without slowing to an unusable crawl.
The development of the new standard for IP began in the summer of 1992 following the first congress of the Internet Society. The Internet Activities Board (IAB) looked at a new standard drawn up by Christian Huitema based on the Connection-Less Network Protocol (CLNP) of the International Standards Organization (ISO). Premature publicity and politics, along with lack of market success of CLNP led to a considerable uproar over whether such a drastic step as definition of a new IP standard should be undertaken without much wider discussion.
From 1992 to 1994, the competing proposals were reviewed, extended, and defined more precisely. The IPng directorate reviewed these proposals in the summer of 1994 and selected SIPP, with some modifications, as the winning proposal. Since the term “IPv5” had already been used for an experimental real-time streaming protocol, the new designation for IPng was IPv6. Another year would pass before the final version of the specification would be agreed upon and published. Training and User Awareness
Early opportunities for personnel involved with network maintenance, configuration, and management to become familiar with IPv6 are already available. They are primarily found in sessions, seminars, and continuing education meetings at various conferences on data communications technology. These began as far back as early 1995. As IPv6 software from telecommunications vendors reaches the market, those vendors will be impelled to provide training in its use, both to support the purchasers and to provide a readier market for the products.
Further, the independent education vendors, such as James Martin Associates, will surely develop courses in which networking personnel may be enrolled. Courses are likely to come in at least two versions: One for those familiar with IP already, and one for those starting from ground zero. In addition, the courses will probably focus separately on the two areas of transition of existing networks to the new regime and that of taking advantage of the new capabilities (autoconfiguration, real-time, anycasting, multicasting) of IPv6.
For example, the University of New Hampshire provides tutorials and short courses in conjunction with its data communications research group, the InterOperability Lab. They offer a number of papers on topics in computing and data communications, including IPv6, in their On-Line Educational Program. The last is even available without charge. In order for a successful transition to IPv6 to take place, the full cooperation of the end-user community is essential. This is a characteristic of most problems in technology transfer called End User Resistance.
Fortunately, the design of IPv6 has kept in mind the need to minimize the impact of the new protocol on end-user operations. One of the keys to solving problems of end user resistance to new information technologies is proper education and training. Even more important is end user involvement in organizational changes and in the development of new information systems. As is usual in technology transfer, the alert manager will plan for advance information briefings long before the date of any transition events.
These briefings will emphasize the minimal impact of the next generation of IP, describe the benefits, and explain the transition plan. The actual transition will be most effectively initiated with a group of early adopters, usually an internal R&D or similar advanced development group used to experimenting with new technology. These participants will assist management both by resolving the problems that inevitably occur in the introduction of a complex of new software and by serving as an additional resource in the romotion and instruction of the larger body of users when the IPv6 implementation is phased in. So designing a program like this to where your recruiting and training employees in the core competencies required for this change in the workplace is effective change management. In change management it’s important to analyze and define all changes facing the organization and developing programs such as the one stated above to where it reduces the risk and costs and to maximize the benefits of the change. Conclusion Many organizations managers, executives etc. re beginning to understand that the availability of improved network is fundamental to successful business. Networks are rapidly increasing in complexity and to organization’s success. For the purpose of increasing network reliability equipment failure needs to be seriously looked into, human error must be reduced to the lowest minimum, construction and design related must leave some rooms for scalability, and external causes must be minimized. As voice and video services are folded into existing data networks, this relationship will become even more profound.
The bottom line regarding management of IPv6 is that there is no real choice about making the transition, other than to decide exactly when this step must be taken. As IPv6 spreads through the Internet, the remaining sites using IPv4 will become increasingly isolated. New network entities will eventually be required to be IPv6 only, making access to them difficult, and tunneling of IPv4 packets between IPv4 sites through the IPv6 environment will experience much poorer performance.
Multimedia applications will increase in importance, and they will depend on the new facilities provided by IPv6 in handling real-time flows. Security considerations will also make continuing in the IPv4 environment increasingly questionable, as vulnerability to address attacks which result in denial of service becomes an unacceptable risk, when IPv6 provides the necessary authentication defense, along with other integrity services. The transition to IPv6 will cost money, take time, require replacement of software, and mean retraining of personnel.
Unlike the year-2000 problem currently receiving much attention and functioning in much the same time frame, this investment will provide some immediate benefits, such as autoconfiguration, more efficient network usage, increased security, and support for real-time flows. IPv6 conversion will leave a site’s current operations mostly unchanged, as far as end-users are concerned, just as replacing current software with software that handles four-digit years provides no immediate functional changes. In both cases, the alternative to conversion is for a site to have no future at some point.
And in that future with IPv6, there are very substantial additional long-term benefits from being able to proceed with development of networked applications without concern that the site will be blocked from participating in the development and expansion of the computing industry and the Internet. References Conner, Douglas E. Internetworking With TCP/IP, 2nd ed. , vol. 1. Prentice-Hall, Upper Saddle River, NJ: 1991 Hinden, Robert M. “IP Next Generation Overview. ” Huitema, Christian. IPv6: The New Internet Protocol. Prentice-Hall, Upper Saddle River, NJ: 1996 Lehtovirta, Juha. “Internetworking: Transition from IPv4 to IPv6. Deering, S. , and R. Hinden, “Internet Protocol, Version 6 (IPv6) Specification”, RFC 1883, August 1996 Thomson, S. , and T. Narten, “IPv6 Stateless Address Autoconfiguration”, RFC 1971, August 1996. McCann, J. , Deering, S. , and Mogul J. “Path MTU Discovery for IP version 6”, RFC 1981, August 1996 Fiuczynski, M. , Lam,V. , and Bershad, B. “The design and implementation of an IPv6/IPv4 network address and protocol translator”, Proceedings of Usenix Annual Technical Conference, June 1998. Aoun, C and Davies, E. “Reasons to move NAT-PT to experimental”, Internet Draft, Jan 2005.
