12-05-2012, 05:29 PM
Internet Protocol
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Definition: IP (Internet Protocol) is the primary network protocol used on the Internet, developed in the 1970s. On the Internet and many other networks, IP is often used together with the Transport Control Protocol (TCP) and referred to interchangeably as TCP/IP.
IP supports unique addressing for computers on a network. Most networks use the Internet Protocol version 4 (IPv4) standards that features IP addresses four bytes (32 bits) in length. The newer Internet Protocol version 6 (IPv6) standard features addresses 16 bytes (128 bits) in length.
Data on an Internet Protocol network is organized into packets. Each IP packet includes both a header (that specifies source, destination, and other information about the data) and the message data itself.
IP functions at layer 3 of the OSI model. It can therefore run on top of different data link interfaces including Ethernet and Wi-Fi.
Definition: IPv6 is the next generation protocol for Internet networking. IPv6 expands on the current Internet Protocol standard known as IPv4. Compared to IPv4, IPv6 offers better addressing, security and other features to support large worldwide networks.
In IPv6, IP addresses change from the current 32-bit standard and dotted decimal notation to a new 128-bit address system. IPv6 addresses remain backward compatible with IPv4 addresses. For example, the IPv4 address "192.168.100.32" may appear in IPv6 notation as "0000:0000:0000:0000:0000:0000:C0A8:6420" or "::C0A8:6420".
The most obvious benefit of IPv6 is the exponentially greater number of IP addresses it can support compared to IPv4. Many countries outside the U.S. suffer from a shortage of IP addresses today. Because IPv6 and IPv4 protocols coexist, those locales with an address shortage can easily deploy new IPv6 networks that work with the rest of the Internet. Experts believe it will take many more years before all networks fully change over to IPv6.
Other benefits of IPv6 are less obvious but equally important. The internals of the IPv6 protocol have been designed with scalability and extensibility in mind. This will allow many different kinds of devices besides PCs, like cell phones and home appliances, to more easily join the Internet in future.
Also Known As: IPng (Internet Protocol Next Generation)
IPv6 is a new and improved version of the IP protocol. In this article, you will learn what IP is, what its limitation is, and how this has led to the creation of IPv6. There is also a brief description of IPv6.
The IP Protocol
IP (the Internet Protocol) is one of the most important protocols for networks, including the Internet. It is responsible for identifying each machine on the network by a unique address (the IP address) and routing data packets from their source to their destination machine through this addressing. The actual version of the IP protocol being used is IPv4 (IP version 4).
The Limitations of IPv4
The structure of a current IP (IPv4) address is four numbers ranging between 0 and 255, each separated by a dot. An example is 192.168.66.1; since each number is represented in binary by an 8-bit word, an IPv4 address is made up of 32 binary digits (bits). The maximum number you can make with 32 bits is 4.3 billion (2 raised to power 32).
Each machine on the Internet should have a unique IP address - no two machines can have the same address. This therefore means that the Internet can theoretically hold only 4.3 billion machines, which is quite a lot. But in the early days of IP, due to lack of vision and some business flair, many IP addresses were squandered. They were sold to companies, which underutilize them. They cannot be claimed back. Some others have been restricted to purposes other than public use, like research, technology-related uses etc. The remaining addresses are dwindling and, considering the amount of user computers, hosts and other devices that are connected on the Internet, we will soon run out of IP addresses!
Enter IPv6
This led to the development of a new version of IP called IPv6 (IP version 6), also known as IPng (IP new generation). You will ask what happened to version 5. Well, it was developed, but remained in the domain of research. IPv6 is the version that is ready to be deployed over the whole Internet and be adopted by all human beings (and any creature) using the Internet and networks. IPv6 brings many improvements, mainly in the number of machines that can be accommodated on the Internet.
IPv6 Described
An IPv6 address consists of 128 bits, therefore allowing an astronomical number of machines. This is equivalent to the value of 2 raised to the power of 128, a number with nearly 40 trailing zeros.
You must now be thinking of the inconvenience of lengthy addresses. This is addressed too - IPv6 address have rules to compress them. First, the numbers are represented in hexadecimal instead of decimal numbers. Decimal numbers are numbers from 0 to 9. Hexadecimal numbers result from the grouping of bits in 4, giving the following characters: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, A, B, C, D, E, F. An IPv6 address is made up of these characters. Since the bits are grouped in 4, and IPv6 address will consist of 32 characters. Long, heh? Well, that's not so serious, especially since there are conventions that help reduce the length of IPv6 address by compressing characters of repetition, for example.
An example of an IPv6 address isfe80::240:d0ff:fe48:4672. This one has only 19 characters - there has been compression, something that goes beyond the scope of this article. Note that the separator has changed from the dot to the colon.
IPv6 not only solves the problem of address limitation, but also brings other improvements to the IP protocol, like autoconfiguration on routers and improved security, among others.
Transition From IPv4 to IPv6
The day when IPv4 will no longer be viable is coming, and now that IPv6 is around, the biggest challenge is to make the transition from IPv4 to IPv6. Imagine renewing the bitumen of a road under heavy traffic. There are many discussions, publications and research work going on and we hope that when the time comes, the transition will work out smoothly.
Who Does What on the Internet?
This is a question many people overlook, as everything is taken for granted. Who developsprotocols like IPv6 and how are all these addresses managed?
The organization that handles the development of protocols and other Internet technologies is called IETF (Internet Engineering Task Force). It consists of members worldwide that meet in workshops several times a year to discuss technologies, from where new technologies or updates stem up. If one day you invent a new network technology, this is the place to go.
The organization that manages the distribution and allocation of addresses and names (like domain names) on the Internet is called ICANN.