Since 1981, TCP/IP has been built on version 4 of the Internet Protocol. IPv4 was created when the giant, world-wide Internet we take for granted today was just a small experimental network. Considering how much the Internet has grown and changed over the course of two decades, IPv4 has done its job admirably. At the same time, it has been apparent for many years that certain limitations in this venerable protocol would hold back the future growth of both Internet size and services if not addressed.
Due to the key role that IP plays, changing it is no simple feat. It means a substantial modification to the way that nearly everything in TCP/IP operates. However, even though we find change difficult, most of us know that it is necessary. For the last several years, development of a new version of IP has been underway, officially called Internet Protocol version 6 (IPv6) and also sometimes referred to as IP Next Generation or IPng. IPv6 is poised to take over from IPv4, and will be the basis for the Internet of the future.
Since 1981, TCP/IP has been built on version 4 of the Internet Protocol. IPv4 was created when the giant, world-wide Internet we take for granted today was just a small experimental network. Considering how much the Internet has grown and changed over the course of two decades, IPv4 has done its job admirably. At the same time, it has been apparent for many years that certain limitations in this venerable protocol would hold back the future growth of both Internet size and services if not addressed. The core problem lies in the 32-bit address space that is too small for the current and future size of the internet and can be addressed only by moving to a larger address space. This was the primary motivating factor in creating the next version of the Internet Protocol, IPv6.
Due to the key role that IP plays, changing it is no simple feat. It means a substantial modification to the way that nearly everything in TCP/IP operates. However, even though we find change difficult, most of us know that it is necessary. For the last several years, development of a new version of IP has been underway, officially called Internet Protocol version 6 (IPv6) and also sometimes referred to as IP Next Generation or IPng. IPv6 is poised to take over from IPv4, and will be the basis for the Internet of the future.
It is important to note that IPv6 is still under development so the points discussed in this post may undergo a change when Ipv6 is finally released. We will look at the major changes expected in the new version of the Internet Protocol.
Some of the most important chnages that will be incorporated in the designing of IPv6 include:
Larger Address Space: This is what we discussed earlier. IPv6 had to provide more addresses for the growing Internet. IPv6 addresses are 128 bits long instead of 32 bits. This expands the address space from around 4 billion addresses to, well, an astronomic number (over 300 trillion trillion trillion addresses).
Better Management of Address Space: It was desired that IPv6 not only include more addresses, but a more capable way of dividing the address space and using the bits in each address.
Elimination of “Addressing Kludges”: Technologies like NAT are effectively “kludges” that make up for the lack of address space in IPv4. IPv6 eliminates the need for NAT and similar workarounds, allowing every TCP/IP device to have a public address.
Easier TCP/IP Administration: The designers of IPv6 hoped to resolve some of the current labor-intensive requirements of IPv4, such as the need to configure IP addresses. Even though tools like DHCP eliminate the need to manually configure many hosts, it only partially solves the problem.
Modern Design For Routing: In contrast to IPv4, which was designed before we all had any idea what the modern Internet would be like, IPv6 was created specifically for efficient routing in our current Internet, and with the flexibility for the future.
Better Support For Multicasting: Multicasting was an option under IPv4 from the start, but support for it has been slow in coming.
Better Support For Security: IPv4 was designed at a time when security wasn’t much of an issue, because there were a relatively small number of networks on the internet, and their administrators often knew each other. Today, security on the public Internet is a big issue, and the future success of the Internet requires that security concerns be resolved.
Better Support For Mobility: When IPv4 was created, there really was no concept of mobile IP devices. The problems associated with computers that move between networks led to the need for Mobile IP. IPv6 builds on Mobile IP and provides mobility support within IP itself.