IPv6 Address Format

IPv6 addresses, unlike IPv4 addresses, consist of 128 bits and are represented as eight sets or fields of 16-bit hexadecimal values (only 0 to 9 and A to F) separated by colons. While case sensitivity is permitted, lowercase is generally preferred for consistency. Each segment is denoted as "x" and takes the form x:x:x:x:x:x:x:x. For instance, one valid IPv6 address would be 2001:0db8:020c:0001:0000:0000:0000:0bbb.

However, as difficult as IPv6 addresses seem, they can be shortened in certain situations when the requirements for that process are met. One requirement is having consecutive zeros in a single field. These zeros can be omitted in such cases, resulting in a shorter version of the same IPv6 address, for instance, 2001:db8:20c:1:0:0:0:bbb. 

In addition, successive fields of 0 can be represented as “::” (double colon). Due to the possibility of ambiguity, this technique allows only one double colon in a valid IPv6 address. As a result, the example IPv6 address from before will be presented in a simplified way, 2001:db8:20c:1::bbb.

All-zero addresses are portrayed with a double colon (“::”), termed the "unspecified address" representation. IPv6's structure accommodates increased device connectivity and offers succinct yet meaningful address notation.