IPv6 is the next version of the Internet Protocol, the data packaging and routing standard on which the Internet is based. The current version is IPv4; IPv5 was experimental and was never widely deployed.IPv6 offers several improvements over IPv4. Most importantly, with 128-bit Internet addresses instead of the 32-bit addresses of IPv4, IPv6 vastly increases the number of addresses available from about 4 billion to about 340 trillion trillion trillion.
Given the continued rapid growth of the Internet, ensuring an abundance of addresses is crucial. The proliferation of wired and (especially) wireless devices means that in the near future not one or two, but many addresses will be required for each person who uses the Internet. The techniques currently employed to cope with the shortage of IPv4 addresses are reaching their limits, and many of these techniques — such as temporary address assignment and network address translation — compromise engineering principles fundamental to the Internet’s success, thus jeopardizing its future growth.
