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.