The Internet Protocol (IP) is the communication protocol used to route traffic across the Internet. The current version, IPv4, was developed in the 1970s and is still the most widely deployed version of the Internet Protocol today. However, IPv4 has some significant limitations, including a limited number of available IP addresses. IPv6 was developed in the 1990s to overcome these limitations and is the designated successor to IPv4.

What are IPv4 and IPv6?

IPv4, which stands for Internet Protocol version 4, is the fourth revision of IP and has been in use since the early days of the internet. IPv4 addresses are 32-bit numbers, which means there are roughly 4.3 billion possible addresses. This may seem like a large number, but with the explosion of internet-connected devices, IPv4 addresses have become scarce. In fact, the exhaustion of IPv4 addresses was predicted years ago, and now there are no more IPv4 addresses available for new devices or networks.

IPv6, on the other hand, is the sixth revision of IP and was designed to address the limitations of IPv4. IPv6 addresses are 128-bit numbers, which means there are approximately 340 undecillion (3.4 x 10^38) possible addresses. This virtually unlimited address space makes it possible to assign unique addresses to an almost infinite number of devices.

The difference between IPv4 and IPv6

IPv4 uses 32-bit IP addresses, allowing for just over 4 billion unique addresses. With the massive growth of the Internet and Internet-connected devices, IPv4 address space is reaching exhaustion. IPv6 uses 128-bit IP addresses, allowing for 3.4x1038 unique addresses. This expansion in address space ensures that IPv6 can support many more digital devices and web services.

Another key difference is that IPv6 addresses are alphanumeric, while IPv4 addresses just consist of numbers. An example IPv6 address could be 2001:0db8:85a3:0000:0000:8a2e:0370:7334. IPv6 addresses are also written differently, with each set of 16 bits separated by colons. The longer length of IPv6 addresses, combined with the alphanumeric characters, make them harder for humans to remember and work with. However, the huge increase in address space with IPv6 outweighs this disadvantage.

IPv6 includes additional features not present in IPv4. This includes mandatory encryption, simpler configuration of IP addressing, and native support for quality of service prioritization. IPv6 is also designed to enable faster routing by simplifying the routing and forwarding process. However, IPv6 is not backwards compatible with IPv4, so both protocols need to be supported in networks and devices during the transition.

Conclusion

The transition to IPv6 has been slow but steady. Most modern operating systems, networking equipment, and web services now support IPv6 by default. However, a full transition will take many more years. IPv4 and IPv6 will likely co-exist together for the foreseeable future. While IPv6 solves many of the challenges of IPv4, its adoption at a global scale will be a long process. Overall, IPv6 is the future of Internet addressing and will enable the next generation of online connectivity.