IP version 6 (IPv6) Advantages and Implementation
IP version 6 is getting a lot of press as of late and possibly for good reason. The Internet
has, to all intents and purposes, run out of public IP version 4 addresses. The Internet Assigned
Numbers Authority (IANA), who is responsible for global address space allocation issued their
last block of IP version 4 addresses in early 2011.
IANA allocates address space to the five regional Internet registries or RIRs who in turn are
responsible for allocating these addresses to requestors, essentially ISPs, in their region. To
date, two of the five registries have run out of allocate-able IP version 4 addresses. While two
out of five sounds fair odds, the two that have exhausted their IP stock cover the Americas and
Europe, making the issue very serious indeed.
While the solution to this issue may seem simple enough - just roll out the new IP version
6 (IPv6) across the Internet and all is well again. Practically this type of implementation
is not that simple and would require a parallel IPv6 based Internet to be running until all
IPv4 connections have been converted. Given the massive scale of the Internet and the speed
with which it is growing, this is going to take some time.
So, while one can see this is a serious issue for the registries and Internet Service
Providers, how does it actually affect the businesses that connect to the Internet?
The answer to this question depends largely on what kind of business one operates. There
are actually good reasons to consider IPv6 in its own right, other than the IPv4 exhaustion
issue, as significant enhancements were made to IPv6 during the design phase. Some of these
enhancements may be of business benefit in the future.
To fully understand the context of the question, however, one needs to delve into a bit
of the detail underpinning IPv6.
IP Version 6, new kid on the block
IPv6 is essentially the replacement protocol for the current IPv4 that drives the Internet,
and pretty much every other network in the world. The most publicised feature of IPv6 is its
massively increased address space. This is possibly its most important feature, as the main
reason behind designing a new version of IP was the imminent exhaustion of old one.
IP has been the de facto standard communication protocol of the Internet since the 1970s
and the address space issue has been a point of concern since the mid 1980s. The IETF
introduced a number of interim measures to help alleviate the issue, Network Address
Translation (NAT) and Classless Inter Domain Routing (CIDR) being the two most pervasive,
but in the end, the 4.3 billion odd theoretical addresses in the IPv4 space was never going to
be enough given the massive growth of the Internet.
While 4.3 billion may sound like a large number, it is worth noting that not all of these
addresses are usable, with only about 3.7 billion being usable individual addresses. Associate
this with the fact that the Internet has been growing at a rate of 100% per annum since 1980,
and has recently increased on this rate, the number starts to look smaller.
In a 2000 interview, Vint Cerf, founder and former chairman of the Internet Society and
man widely considered to be the "inventor" of the Internet made the following prediction:
"Projections of Internet growth suggest that there will be 900 million servers among
a total of 2.5 billion total devices on the Internet by 2006 - the latter number including
about a billion and a half Internet-enabled mobile telephones.
"By 2010, half the world's population may be able to access the Internet, if present
rates of growth continue unabated. By that time, some estimates of connected devices
of all kinds reach 35 billion (nearly 6 devices per person on the planet!).
"That this may not be completely insane is illustrated by the fact that in 2000, a person
with a laptop, personal digital assistant and a cell phone may already have three devices
on the Internet. When one starts adding household and office appliances (e.g., facsimile
machines, printers, refrigerators, televisions and video cassette recorders), it is not hard
to see how the numbers might add up.
"Of course, the averages will be skewed to much higher numbers in the most networked
parts of the world (North America, Europe, Australia, Japan, parts of India and the Pacific Rim)
and smaller numbers in the less networked parts"
While the prediction of 35 billion connected devices may sound a bit aggressive, clearly
Vint Cerf was not far off given the fact that we have essentially run out of IPv4 addresses
a little more than two years later than he predicted.