Prior to implementation of IPv4, engineers and scientists working on ARPANET debated on the length of an IP address. The debate was between 32-bit and 128-bit address lengths. Although the consensus was 128-bit, Vint Cerf, in 1977, made the decision to use a 32-bit length for the IPv4 address. He made this decision because he never foresaw the need for more than 4.3 billion address and wanted to move the project forward [1]. Thus, IPv4 was to be 32-bits long and the internet was born. On the 3rd of February 2011, the Internet Corporation for Assigned Names and Numbers (ICANN) handed out the last block of the IPv4 addresses [2].
The resulting scarcity of IPv4 address blocks leads to gradual depletion of IPv4 address space. In order to save and reuse the address blocks, service providers (SP) resort to mechanisms like multiple layers of Network Address Translation (NAT). The more ideal approach to solve the issue of address scarcity facing the networking industry is to move towards the IPv6 addressing scheme.
IPv6 provides 3.4 x 1038 addresses and comes with other additional improvements. First, it provides increased efficiency in routing. Second, it provides faster packet processing. Third, it supports multicast thereby overpowering the hassles of broadcasting packets. Fourth, it avoids network address translation (NAT), therefore, proves to be more robust [3].
IPv6 adoption has been slow and faces numerous obstacles. First, there is no true financial driver for companies. The exhaustion of IPv4 address space has been advertised for years and the industry has developed technology to extend IPv4 address usage. The most popular of these technologies is Network Address Translation (NAT). NAT helped to push out the exhaustion of IPv6 by roughly a decade. This has bought time for IPv6 to mature further.
During this year’s world IPv6 day, the goal is to enable approximately one percent of the Internet with IPv6 support. This is not an estimate of actual IPv6 traffic. The experts expect IPv6 traffic to increase exponentially in the coming years.