Computer networks rely on TCP / IP protocols. This model represents all the rules of communication on the Internet and uses the notions of routing addressing. Given the increase in the number of machines the IPv4 protocol will be a victim of its success and will no longer meet the demand for connection of billions of computerized machines and other equipment available to the Internet users of tomorrow. So a new version of protocol (IPv6) came into existence. The next generation IP, IPng (next generation) or IPV6 will offer new addressing capabilities, security options and many other features (routing, Web services and DNS) that will facilitate global interconnections.
What is it ?
IPv6 is a new generation of Internet protocol that follows the IPv4 type. This new generation Internet protocol brings a much larger address space than IPv4.
The main objectives of this new protocol will be to :
o Support billions of computers, freeing itself from inefficient IP address space.
o Reduce the size of the routing tables.
o Simplify the protocol, to allow routers to route datagrams faster.
o Provide better security (authentication and confidentiality) than the current IP protocol.
o Pay more attention to the type of service and especially the services associated with real-time traffic.
o Facilitate multicast distribution by specifying the scope.
o Give the possibility to a computer to move without changing its address.
o Allow the protocol a future evolution.
o Grant old and new protocol a peaceful coexistence.
The transition from an IPv4 network to an IPv6 network is expected to last a very long time. It is therefore necessary during this transition period to allow IPv4 and IPv6 machines to coexist and communicate with each other.
To facilitate this transition, several solutions are proposed. They are based on the following principles :
- The technique of double stack (Dual-Stack). IPv4 and IPv6 coexist on the same node.
- Tunnel techniques that encapsulate the original datagram in the destination protocol.
- Translation techniques that adapt the datagram to the protocol of the target network (protocol conversion).