What Is IPv6 (Internet Protocol Version 6)?

IPv6 overcomes the lack of IPv4 addresses and provides a larger address space to accommodate the growing number of internet-connected devices. It offers many improvements and additional features which generally advance internet communication.

IPv6 addresses are 128 bits long, represented as eight groups of four hexadecimal digits separated by colons, such as 2001:0db8:85a3:0000:0000:8a2e:0370:7334. Bits are binary digits that are the smallest increment of data on a computer. The expanded address space of IPv6 allows for approximately 340 undecillion (3.4 x 10^38) unique addresses, ensuring that every device can have a globally unique identifier.

Read more: Information Technology (IT) Terms: A to Z Glossary

IPv6 benefits

The increased address space in IPv6 eliminates the need for techniques like network address translation (NAT), which are commonly used in IPv4 to conserve address space. NAT allows multiple devices to share a single public IP address, but it introduces complexity and can cause issues with certain applications. With IPv6, each device has its own public IP address, simplifying network configurations and facilitating direct end-to-end communication. Here are additional benefits that IPv6 offers include the following: 

• IPv6 offers a simpler and more efficient header than the IPv4 header, resulting in faster routing and improved network performance. It also supports more efficient packet handling, eliminating the need for header checksums at every intermediate hop.

• IPv6 introduces built-in support for security through IPsec (internet protocol security). IPsec provides encryption and authentication at the network layer, ensuring secure communication between devices. While IPsec was optional in IPv4, it is an integral part of IPv6, enhancing privacy and data integrity across the internet.

• IPv6 incorporates features that support mobility and auto-configuration. Devices on Mobile IPv6 are able to move between different networks without losing connectivity, allowing for uninterrupted communication while on the move. 

• IPv6 also includes stateless address auto-configuration (SLAAC), which allows devices to generate their own IPv6 addresses and obtain necessary network information without relying on external configuration servers.

Transitioning to IPv6

The transition from IPv4 to IPv6 is an ongoing process. Many organizations and internet service providers (ISPs) have started deploying IPv6 infrastructure to ensure compatibility and future-proof their networks. However, complete IPv6 adoption requires the cooperation and support of all network stakeholders, including internet service providers, hardware manufacturers, software developers, and end-users.

IPv6 examples

IPv6 addresses are in hexadecimal notation and divided into eight groups of four hexadecimal digits separated by colons. Each group represents 16 bits, resulting in a total of 32 characters in the address. It doesn’t need leading zeros within each group, and you can compress consecutive groups of zeros by using a double colon (::), but this abbreviation can only be used once in an address.

For example, consider the following IPv6 address: 2001:0db8:85a3:0000:0000:8a2e:0370:7334. In this address, each group of four hexadecimal digits represents 16 bits. The leading zeros within each group are not necessary, resulting in the address 2001:db8:85a3:0:0:8a2e:370:7334. Additionally, a double colon (::) can replace consecutive groups of zeros, but only once. Thus, the address can be further abbreviated as 2001:db8:85a3::8a2e:370:7334.

Related terms

• CPU

• BIOS

• CIDR

• TCP/IP

• Operating system

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