An address fulfills the functions of identifying the host and locating it on the network. The most common network addressing architecture is Internet Protocol version 4 (IPv4), but its successor, IPv6, has been increasingly deployed since approximately 2006. An IPv4 address consists of 32 bits, for readability written in a form consisting of four decimal octets separated by dots, called dot-decimal notation. An IPv6 address consists of 128 bits written in hexadecimal notation and groupings of 16 bits, called hextets, separated by colons.