How many unique addresses are supported by IP version 6?

IP version 6 (IPv6) was designed to vastly expand the number of unique IP addresses available compared to its predecessor, IPv4. The IPv6 addressing scheme utilizes 128 bits for each address. This means that the total number of unique addresses is calculated as 2 raised to the power of 128.

To understand this further, each bit in an address can have two possible values (0 or 1), and with 128 bits, the total combinations or possible unique addresses becomes 2^128. This enormous capacity allows IPv6 to accommodate a virtually limitless number of devices connected to the internet, reflecting the growing need for more addresses as the number of internet-connected devices continues to increase.

Other options do not reflect the correct number of unique addresses supported by IPv6, as they either represent the address spaces of other protocols or are incorrect mathematical calculations regarding the capacity of IPv6.