Before taking the Cisco Certified Network Associate exam, or CCNA, it is absolutely essential to understand both the "why" and the "how" of the new and emerging IPv6 technology. This is a crucial part of the exam and, as the future of the internet in generally, it's pretty important to understand how it works. Before that, though, it's even more important to understand why there is even a need for IPv6 technologies, as well as how they're implemented in a world that has largely been completely constructed based on the IPv4 specification.
Looking at the Origins of the IPv4 Specification
Even though the actual use of IPv6 in real world applications is relatively new, its roots begin more than two decades ago in 1990. That was the first year when tech experts began to predict that IPv4 address space would actually run out do the explosive growth of connected devices. Even in a world that couldn't foresee the coming smartphone and tablet revolution that enabled "everything everywhere" connectivity, this was a real concern.
In 1992, IPv4 classes A, B, and C, were joined by CIDR, or Classless Internet Domain Routing. This technology was essentially developed to promote greater efficiency within IPv4 environments, allowing blocks to be assigned more slowly and preventing the IP catastrophe that many analysts were predicting at the time. While this was a great way to "kick the can down the road," it was not a permanent solution.
Steps toward a more lasting solution began in 1993, when the Internet Engineering Task Force recognized the need for an entirely new protocol that would highly scalable in a world full of connected devices. In response, the IETF created the IP Next Generation Group to study, analyze, and plan the deployment of a new IP protocol that would last far longer than the aging IPv4. The group became known as IPng, and it got to work pretty quickly. By 1994, the group's work was being approved and standardized by a number of internet standards committees, and it was officially given the IPv6 designation later that year.
Test implementations followed fork the next half-decade and, in 1999, regional internet registries assigned the first block of IPv6 addresses for non-experimental uses. This followed the releasing of patches and operating system updates to enable the parsing and processing of IPv6 address blocks just a few years earlier, and the technology was officially on its way.
Examining the Need for a New IP Address Specification
It was more than 20 years ago that experts first predicted that IPv4 address blocks would run out. The assignment of these addresses, and the relative lack of new ones to assign, has increased exponentially in the last decade alone. In 2002, a full 28 percent of IPv4 address blocks were still available for use around the world. By the present decade, that number had dropped by nearly two-thirds to just 10 percent. Without the development of the IPv6 specification, the future of the internet would currently be experiencing a real threat to its continued viability and use.
The IPv4 specification is a 32-bit construction, which allows for a grand total of 4,294,967,296 address blocks before the system simply runs out of options and capacity. Comparatively, IPv6 specification employes a 128-bit structure which permits for a vastly larger sea of potential address blocks. Indeed, the total number of IPv6 address blocks available for allocation around the world is 3.4 x1038, which experts believe can last anywhere from a few decades up to a half-century before a more advanced standard needs to once again be developed due to rising demand and a dearth of available blocks.
The IPv6 specification is also far more engaged with advanced hierarchies that make internet routing more efficient. This is seen as one of the main problems with IPv4, especially given the exponential growth of the internet and connected devices over the past two decades. The technology is not only much more vast and available, but actually faster at doing the exact same tasks that the IPv4 table is currently charged with handling.
A Commitment to Global Fairness with IPv6 Technologies
One of the interesting things about IPv4 is that the technology was actually split among several global governing bodies that served specific regions of the planet. Each governing authority managed the granting and distribution of IPv4 blocks to every country within its purview, and the structure still being used looks like this:
- ARIN, for North America, the Caribbean, and some North Atlantic locations
- AfriNIC, serving the African continent and Indian Ocean island nations
- APNIC, for the Asia-Pacific region and Oceania
- LACNIC, for South America and non-ARIN parts of the Caribbean
- RIPE NCC, for Europe and the Middle East
Despite these five organizations and their relatively equal holdings around the world, the ARIN organization is responsible for granting a full 74 percent of the IPv4 address blocks currently in use. That's an astounding disparity between the regions, and it's something that IPv6 has aimed to fix with the way it is deployed. Unlike IPv4, the technology has a single and global granting body, as well as a global prefix structure, that is designed to promote greater fairness in the assignment of addresses.
Where is IPv6 Now, and Where Will it Go in the Future?
Presently, much of the world is still stuck on the IPv4 standard as governments and internet service providers slowly migrate to the newer standard. While much of China and Korea are both running on the IPv6 standard for both traditional and mobile internet devices, the United States has lagged behind in implementation. The federal government announced a goal to be compatible with the technology by 2008, and has largely met that standard; the wireless provider T-Mobile has deployed IPv6 to its mobile networks; but other than these two major developments, the United States still relies heavily on IPv4. This partially makes sense, however, given that the continent is responsible for 74 percent of the specification's allocation around the world.
Looking to the future, IPv6 adoption will increase because it has to. While it is currently "dual stacked" with IPv4 address blocks, that will change as IPv4 addresses simply run out and people around the world are forced to migrate to the newer standard. Given the fast rate of IPv4 address disbursement, this is likely to happen within the present decade.
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