The world used to have 4 billion IP addresses in stock with IPv4 but this number dangerously decreases. The total shortage could come in the second half of 2010.
90% of IPv4 addresses already used - This figure comes from the Number Resource Organization, a non-profit organization in charge of taking care of a disappearing resource: Internet Protocol addresses. According to the NRO study, the shortage could occur very soon: in the second half of 2010.
Actually, IPv4 is the widespread protocol. It is used to put into communication the vast majority of the equipment in the world network. IPv4 format consists of four numbers separated by dots, ranging from 0 to 255. Since 300 million IP addresses are not available (used by private networks), if we calculate, it left us with 4 billion addresses- at the beginning.
Mobile machines accelerate the shortage - The problem is that devices connected to the Web are increasing in an exponential way. This situation can be explained by a mass access to the Internet for businesses and individuals and now the proliferation of mobile devices connected. In Europe or in the USA for example, a person may use several IP. This is the way we have come to only 10% unallocated today. Furthermore, the stock of free addresses may disappear even faster since the scarcity triggers a speculative fever at this time.
IPv6 to the rescue - One solution to this problem is named IPV6. This new version, more secure and sustainable, multiplies the number of available IP addresses. However, the total changeover from one version to another will pose more of a problem: the migration will be gradual, very costly for operators, and should take account of hardware incompatibilities due to the age of some machines.
Other solutions to manage the shortage would be the massive use of sub-networks, address translation, and also to recover the numerous addresses which was assigned a long time ago and which are unused.
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