TCP/IP (Version 4) is the network protocol used by most networks, including the internet. Essentially a network protocal is a set of rules that define how computers find each other and exchange information.
When you open a web browser and type in the name of a website, your browser asks an internet name server for the network address of the server with the name you entered, then makes a seperate request for the page you requested from the server at that IP address. Any request that your computer makes has to be translated to a network address before it can be sent to a server. Your computer does the translation for you, and usually hides the details.
The IPV4 addressing scheme takes the form of 4 numbers between 0 and 255 seperated by dots. this allows the protocol to theoretically identify over 4 billion computers. The theoretical limit is not really attainable, because a lot of the possibilites are reserved to allow the networking equipment of the internet to direct traffic based on the first parts of the address. There are also ranges of addresses reserved for other reasons. In practical terms the number of usable addresses is much smaller than the full range.
There was some panic when the internet was undergoing very rapid expansion in the late 1990′s that the addressing scheme would run out of addreses, and that it would not be possible to add new computers to the internet. This concern was accompanied by a rush to define and implement a new protocol that included a much larger address space. When the danger of running out of addresses did not materialize, the rush toward IPV6 slowed down.
Some of the factors that kept the internet from running out of addresses were: the rapid expansion of IP address needs dropped off from the projected curves of the late 1990′s; the addressing scheme was modified to allow some of the otherwise unusable blocks of addresses to be usable; and the general adoption of NAT and/or firewall devices connect large numbers of computers to the internet using a single IP address.
IPV6 is a new protocol, with a new addressing scheme for networks. The addressing scheme is not the only advantage of the new protocol, but has been the biggest driving force behind it’s adoption.
If IPV6 is better, why isn’t everyone already using it?
There are a number of barriers to implementing IPV6. One of the biggest barriers was removed earlier this year, when the top level domain controllers for the internet began supporting IPV6 addresses. To take advantage of that, internet service providers will need to acquire IPV6 addresses for their servers, implement IPV6 on the servers, and add the new addresses to their own and the top level name servers.
Most network equipment and most servers can support the IPV6 protocol to some extent, since the preparations began so long ago, but implementing a new protocol is a lot of work for the network and server administrators. They need to configure the equipment, aquire and and plan allocations for the new address ranges, configure servers to take advantage of the new IPV6 features, and test everything with both IPV4 and IPV6 clients.
There is also an element of ‘letting everyone else go first.’ Since any benefit of IPV6 will be seen only when the entire transaction chain (Client, ClientISP, Internet, ServerISP, Server) have implemented IPV6, there is no upside to updating an internet service until a significant number of clients are using IPV6 or any upside for an ISP until there are significant services available in IPV6.
The biggest downside I see is that there doesn’t seem to be any benefit to the end consumer. The new address scheme will result in the absolute identification of a particular computer in all it’s transactions, which most consumers would see as a downside, both in the reduction of their percieved anonymity, and exposure to direct attacks from hackers, while most of the issues that absolute identification would solve have already been addressed in NAT and Firewall solutions.
Until the benefits of adding or switching to IPV6 outwiegh the cost of doing so, most of the internet will continue to communicate with IPV4. In any case, unless you are a network engineer or web service administrator, you probably would not notice a difference.
