Final answer:
An IPv6 address consists of eight groups of four hexadecimal digits, with each group separated by colons.
Step-by-step explanation:
The IPv6 addressing system uses 128-bit addresses which are represented as eight groups of four hexadecimal digits. Each group of four hexadecimal digits is separated by colons. To calculate how many groups of four hex digits back up an IPv6 address, we need to understand the structure of an IPv6 address. An IPv6 address is divided into eight 16-bit blocks, and each 16-bit block is represented by four hexadecimal digits, which is why they are known as groups of four hex digits.
In summary, an IPv6 address consists of eight groups of four hex digits. Hexadecimal digits range from 0 to 9 and from A to F, representing the numbers 10 to 15. For example, an IPv6 address might look like this: 2001:0db8:85a3:0000:0000:8a2e:0370:7334, which clearly shows the eight groups.