IPv4 CIDR Down to Less than 10% Left
With less than 10% of IPv4 address space remaining, organizations must adopt IPv6 to support applications
that require ongoing availability of contiguous IP addresses, says the American Registry for Internet Numbers which appeared at the recent CTIA Show in Las Vegas.
Internet Protocol defines how computers communicate over a network. IP version 4 (IPv4), the currently prevalent version, contains just over four billion unique IP addresses. IPv6 is a newer numbering system that provides a much larger address pool than IPv4, among other features.
Classless Inter-Domain Routing (CIDR) is a methodology of allocating IP addresses and routing internet protocol packets. It was introduced in 1993 to replace the prior addressing architecture with the goal to slow the growth of routing tables on routers across the Internet, and to help slow the rapid exhaustion of iPv4 addresses.
IPv4, which was deployed in 1981, has just over 4.2 billion available CIDR prefixes in it.
The new IPv6, first deployed in 1999, has this many CIDR prefixes in it:
340,282,366,920,938,463,463,374,607,431,768,211,456
That should be enough to last a little while longer.
