IPv6, short for Internet Protocol Version 6, is a next generation communications protocol created by the Internet Engineering Task Force to replace the current IPv4. Because Internet traffic requires unique sender and receiver addresses and the number of users has grown exponentially, more addresses are required than IPv4 can support.
Every address under IPv4 is 32 bits long, allowing for a maximum of 4.3 billion unique addresses. The IPv6 address format is 128 bits long, increasing the number of available addresses enough to allow 100 unique addresses to be assigned to every atom on the face of the Earth. However, as of September 2013, only 4 percent of Internet domains and 12 percent of the networks in the world support IPv6.