About IPv6
Internet Protocol version 6 (IPv6) is the latest version of the Internet Protocol (IP), and provides an identification and location system for computers on networks and routes traffic across the Internet.
IPv6 permits hierarchical address allocation methods that facilitate route aggregation across the Internet, and thus limit the expansion of routing tables. The use of multicast addressing is expanded and simplified, and provides additional optimization for the delivery of services.
IPv6 is based on IP but with a much larger address space and improvements such as a simplified main header and extension headers. The IPv6 address space allows networks to scale and provide global reachability.
The primary motivation for IPv6 is the need to meet the demand for globally unique IP addresses. IPv6 quadruples the number of network address bits from 32 bits (in IPv4) to 128 bits, which provides more than enough globally unique IP addresses for every networked device on the planet. By being globally unique, IPv6 addresses inherently enable global reachability and end-to-end security for networked devices, functionality that is crucial to the applications and services that are driving the demand for the addresses. Additionally, the flexibility of the IPv6 address space reduces the need for private addresses and the use of Network Address Translation (NAT); therefore, IPv6 enables new application protocols that do not require special processing by border routers at the edge of networks.