Continution of IPv6
That
short-term solution was (NAT), which allows multiple hosts to share one or a few public IP
addresses. Behind the NAT device, private IP addresses are used.
NAT has been so successful in slowing IPv4 address depletion, and has become such a standard part of most networks, that to this day many still question the need for a new version of IP. But the widespread use of NAT has changed the open, transparent, peer-to-peer Internet into something much more like a huge collection of client-server networks. Users are seen as being connected around the "edge" of the Internet, and services flow out to them.
Although most of the IPv6 standards were completed years ago, it is only recently that serious interest in migrating from IPv4 to IPv6 has been shown. There are two fundamental drivers behind the growing recognition of the need for IPv6.
The first is widespread vision of new applications using core concepts such as mobile IP, service quality guarantees, end-to-end security, grid computing, and peer-to-peer networking. NAT stifles innovation in these areas, and the only way to get NAT out of the way is to make public IP addresses abundant and readily available.
The second fundamental driver for IPv6 is the rapid modernization of heavily populated countries such as India and China. A compelling statistic is that the number of remaining unallocated IPv4 addresses is almost the same as the population of China: about 1.3 billion. With its aggressive expansion of its Internet infrastructure, China alone in the near future will represent an unsupportable pressure on an already strained IPv4 address pool. In India, with a population size close to China's, 4- and 5-layer NAT hierarchies exist just to support the present demands for IP addresses.
IPv6 replaces the 32-bit IPv4 address with a 128-bit address, making 340 trillion trillion trillion IP addresses available. That number will meet the demands for public IP addresses, and answer the needs of the two fundamental drivers discussed here, well into the foreseeable future
NAT has been so successful in slowing IPv4 address depletion, and has become such a standard part of most networks, that to this day many still question the need for a new version of IP. But the widespread use of NAT has changed the open, transparent, peer-to-peer Internet into something much more like a huge collection of client-server networks. Users are seen as being connected around the "edge" of the Internet, and services flow out to them.
Although most of the IPv6 standards were completed years ago, it is only recently that serious interest in migrating from IPv4 to IPv6 has been shown. There are two fundamental drivers behind the growing recognition of the need for IPv6.
The first is widespread vision of new applications using core concepts such as mobile IP, service quality guarantees, end-to-end security, grid computing, and peer-to-peer networking. NAT stifles innovation in these areas, and the only way to get NAT out of the way is to make public IP addresses abundant and readily available.
The second fundamental driver for IPv6 is the rapid modernization of heavily populated countries such as India and China. A compelling statistic is that the number of remaining unallocated IPv4 addresses is almost the same as the population of China: about 1.3 billion. With its aggressive expansion of its Internet infrastructure, China alone in the near future will represent an unsupportable pressure on an already strained IPv4 address pool. In India, with a population size close to China's, 4- and 5-layer NAT hierarchies exist just to support the present demands for IP addresses.
IPv6 replaces the 32-bit IPv4 address with a 128-bit address, making 340 trillion trillion trillion IP addresses available. That number will meet the demands for public IP addresses, and answer the needs of the two fundamental drivers discussed here, well into the foreseeable future
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