When IPv4 was designed in the late 1970s with a 32 bit address field, there were over 4.3 billion addresses allocated and the thought was that this number would be sufficient for a very long time. But this was before the Internet and mobile phones, which has consumed all the available IPv4 addresses. As of February 2011, the last available blocks of IPv4 addresses were distributed to the regional IP address authorities around the world and these blocks will be allocated to ISPs during the remainder of 2011. By the end of 2011, there will be no more IPv4 addresses available anywhere.
2. Plenty of IPv6 addresses
With the world running out of IPv4 addresses, the Internet Engineering Task Force (IETF) in the early 1990s decided to design a replacement. They settled on IPv6 with an address space of 128 bits, which is 2 to the 128th power, or 10 to the 37th power. This should be sufficient to address every atom in the universe, so there is very little likelihood of running out of addresses in the foreseeable future.
3. What you can do with an IPv6 address
IPv6’s design cuts down on the time network administrators have to spend configuring and managing network devices. IPv6 networks use stateless address auto-configuration to assign addresses without manual intervention. In stateless IPv6 addressing, network equipment automatically assigns a unique IPv6 addresses, which will eliminate the need to worry about setting up IP addresses. Your hardware will do it for you.
Of course, you can use Dynamic Host Configuration Protocol (DHCP) to do that on IPv4-based business LANs today. But, with DHCP you can only assign unique addresses within your own network. DHCP and NAT (Network Address Translation) gets in the way when you try to use Internet applications like videoconferencing, Voice over Internet Protocol (VoIP), Peer-to-Peer (P2P) applications, and the like. As a user you usually don’t see these problems, unless your application fails. But trust me, anyone who programs for the Internet loathes having to jump through hoops to get their applications to work through NAT. With IPv6, though, every device on every network has a unique, universal Internet IP address, and both developers and network administrators will no longer have to waste time getting network applications to work around NAT.
4. You can't stay on IPv4 forever
IPv4 is imcompatible with IPv6. For the next few years, as companies convert their infrastructure to dual-stack IPv4-IPv6 systems, IPv4-only systems will still be able to reach other IPv4 systems. However, as more and more systems reach their end of life and IPv6 becomes more prevalent, IPv4 systems and networks will be turned off, leaving IPv4-only systems without connectivity to IPv6-only networks. Maintaining and operating dual-stack IPv4/IPv6 systems and networks is expensive, so there is an incentive to move to an IPv6-only infrastructure as soon as possible.
5. Security advantages of IPv6
A major advantage of IPv6 is that Internet Protocol security (IPSec) is required and an integral part of the IPv6 protocol. IPSec had existed before but was optional in IPv4. IPSec is comprised of open standards for protecting communications over TCP/IP networks. IPSec is used in conjunction with cryptographic security mechanisms for virtual private networks (VPNs). IPSec also supports network-level encryption and peer authentication, as well as data origin authentication using Internet Key Exchange (IKE) and Public Key Infrastucture (PKI). The net result is that IPSecmakes all Internet traffic safer, since IPv6 can secure and authenticate communications at the network layer, instead of the higher levels of the stack such as Secure Sockets Layer (SSL) and Hypertext Transfer Protocol Secure (HTTPS).
6. IPv6 mobility features
Another major feature of IPv6 addressing is that when moving from place to place with your IPv6-enabled mobile device, you’ll no longer need to worry about getting a new Internet address at every stop. With Mobile IPv6, as you move from one location to another, IPv6 uses its network discovery and stateless auto configuration features to seamlessly maintain connectivity, while retaining your same address. This is a huge advantage, since not only will IPv6 preserve end-to-end connectivity while on-the-go between networks, but no manual IP address configuration is ever required.
7. IPv6 Multicast capabilities
IPv6 is also designed for real-time video and communications. IPv6 comes with built-in support for multicast, which is the transmission of a single datagram to multiple receivers. IPv4 has some multicast capabilities, but these are optional and not universally supported. With IPv6, multicast is part of the protocol. This will make transmitting video over the Internet, which is becoming ever more popular, a lot easier for video content providers.
8. You can migrate to IPv6 gradually and safely
For several years, major operating systems, such as Windows Vista, 7 and MAC OS X have been IPv6-capable. With a slight investment in infrastructure and training, you can gradually start migrating to IPv6 to gain experience on how to operate in an IPv6 world. For some systems, they can be easily upgraded to a new operating system. For older systems, an upgrade to a newer OS is not possible or may be cost-prohibitive due to incompatibilities in HW or application code. Some applications may be tied to one particular OS and/or HW platform and upgrading to IPv6 might entail wholesale replacement of the HW and OS, not to mention changes in the SW application. For these reasons, several mechanisms have been devised to connect IPv4-only systems with IPv6 systems. Tunnelling only allows like systems to talk to each other, so IPv4-only systems can tunnel packets through an IPv6 network to reach other IPv4-only systems. Dual-stack implements both IPv4 and IPv6 protocol stacks on the same machine, so for awhile, it may be possible to have IPv4-only systems talk to dual-stack systems. But for the day when dual-stack systems become IPv6-only, those IPv4-only systems will be left stranded. That's why there is another class of IPv6 transition mechanisms known as translators that can provide connectivity between IPv4-only systems and IPv6-only systems. In essence, they are protocol translators with the added benefit of providing IPSec security and multicast to the IPv4-only device.
9. IPv6 is required for sale to US Federal Government
Since 2008, all products bought by the U.S. Government and Department of Defense must be IPv6-capable. Federal Acquisition Requirements (FAR) rules were changed mandating this change. So, if your company's products are IPv4-only and you wish to sell them to the U.S., you have to make them IPv6-capable. This may require a change to the application code, operating system or hardware. This may entail major delays, risk and expense. An alternative to changing your IPv4-only product would be to couple it with an IPv4-IPv6 translator that has been approved for U.S. Government sale. Your product and the IPv4-IPv6 translator would qualify it as IPv6-capable.
10. The rest of the world is moving to IPv6
When IPv4 addresses were first allocated in the 1970s, the U.S. got most of the addresses. Since then, the rest of the world has had to make do with a smaller allocation of IPv4 addresses, so for them, IPv6 was the only viable alternative moving forward. Starting several years ago, many countries, such as China, Japan and Korea made investments in IPv6, so that today they have nationwide IPv6 addresses. In order to be compatible with the rest of the world, the U.S. and U.S. companies must make the investment to move to IPv6.
