IPv6(Internet Protocol
Version 6) will succeed IPv4 (Internet
Protocol Version 4) which is currently the internet protocol used all over
the World by June 6,2012 .
Each host ,computer or other device on the Internet requires an IP address in order to communicate. The explosive growth of the Internet over the last decade has created a need for more addresses than are possible with IPv4.
Like IPv4, IPv6 is an internet-layer
protocol for packet-switched internetworking and provides end-to-end datagram
transmission across multiple IP networks. While IPv4 allows 32 bits for an IP
address, and therefore has 232 (4 294 967 296) possible addresses,
IPv6 uses 128-bit addresses, for an address space of 2128
(approximately 3.4×1038) address.
IPv6 will make not much difference to most
users because they will most probably continue to use IPv4 by default, as the
switch to IPv6 is possible only when their computers, the networks and the
content and service providers are ready for it.
IPv6 also implements additional features not present in IPv4.
It simplifies aspects of address assignment (stateless address
autoconfiguration), network renumbering and router announcements when changing
network connectivity providers.
The IPv6 subnet size
has been standardized by fixing the size of the host identifier portion of an
address to 64 bits to facilitate an automatic mechanism for forming the host
identifier from link-layer media addressing information (MAC address). Network
security is also integrated into the design of the IPv6 architecture, including
the option of IPsec.
For the Internet to make use of the advantages of IPv6 over
IPv4 :
- Most hosts on the Internet, as well as the networks connecting them, need to deploy this protocol. However, IPv6 deployment has been slow.
- While deployment of IPv6 is accelerating, especially in the Asia-Pacific region and some European countries, areas such as the Americas and Africa are comparatively lagging in deployment of IPv6.
- IPv6 does not implement interoperability features with IPv4, and creates essentially a parallel, independent network. Exchanging traffic between the two networks requires special translator gateways, but modern computer operating systems implement dual-protocol software for transparent access to both networks either natively or using a tunneling protocol