What is the maximum length of an IPv6 address?

An IPv6 address is defined to be 128 bits in length, which allows for a significantly larger address space compared to its predecessor, IPv4. This expansion in address size accommodates the growing number of devices connected to the internet and the need for unique addresses. Specifically, a 128-bit address consists of eight groups of four hexadecimal digits, separated by colons.

This large address space enables the assignment of approximately 340 undecillion unique addresses, providing ample opportunities for addressing in networks, including those for future technologies like the Internet of Things (IoT).

The incorrect options reflect the lengths associated with older addressing schemes or smaller address spaces that do not meet the requirements of modern networking. For example, the 32-bit and 64-bit lengths are typical of IPv4 and certain types of network configurations or protocols but do not correspond to the IPv6 standard. The 256-bit option exceeds the defined length for IPv6, which is specifically set at 128 bits.