IPv6

Counting the days of IPv4

Who said that the world won't need 4,294,967,296 ip addresses? Well, this might be what they thought when they designed the first Internet Protocol which is commonly known as IPv4 (RFC 791). But today, the use of IPv4 address has grown exponentially which led to a rapid decrease of available ip address. JPNIC or Japan Network Information Center has released a statement about IPv4 consumption that the pool of IPv4 address is expected to run out this coming 2010
(http://www.apnic.net/news/2007/0626.html). It may not exactly fall on 2010 but truth about IPv4 address exhaustion is presistent and it will happen 2 to 4 years from now.

Why an exponential growth? Aside from the rapid growth of Internet users, you can find IPv4 address almost anywhere now. Your GPRS enabled mobile phone has an ip address and in some part of world even automobiles and home appliances can be connected and be monitored and controlled over the internet (http://www.pcmag.com/article2/0,1759,110893,00.asp).

So what if the IPv4 reaches its end? There is no need to panic, the Internet Engineering Task Force (IETF) has already designed the Next Generation Internet Protocol 10 or 12 years ago. They call it Internet Protocol Version 6 or IPv6.

IPv6 to the rescue

This is the number of available IPv6 address the world can have 2^128. This is about 3x10^38 (340,282,366,920,938,463,463,374,607,431,768,211,456) ip addresses. Still it is a finite value though, but IPv6 architects said that this number should be enough for you to have your own PAN (Personal Area Network) in which even your underware is assigned with an IPv6 address.

How is this next generation address represented? If the IPv4 address which is 32-bit long was simplified by grouping it into octets(8-bits) separated with a dot(.) and represent each octet with its equivalent value in decimal, IPv6 address which is a 128-bit address is divided into 8 16-bit fields. The separator used in IPv6 is a colon(:) and represent each 16-bit number into a 4 digit hexadecimal value. A sample IPv6 address representation is 2001:0db8:abcd:00ef:0000:0000:0000:0001.

An IPv6 address has three categories just as we have IPv4 classes. The three categories are, IPv6 Unicast Address, IPv6 Multicast Address and IPv6 Anycast Address. An IPv6 unicast address can be used as an identifier for a single interface, an IPv6 anycast address can be used as an identifier for a set of interfaces, while an IPv6 multicast address can be used as an identifier for a group of nodes.

IPv6 Advantage over IPv4

Looking at the figures, we can directly identify that IPv6 offers a much larger IP address space than IPv4. With this, it is certain that IPv6 can be the solution of the IPv4 address depletion problem. The IPv6 address architecture is also more efficient and hierarchical than the IPv4 address. This will solve the currently increasing backbone routing table size. Lastly, IPv6 address was designed with some built-in features such as security, stateless address autoconfiguration, multicast, QoS (Quality of Service) and more.