<P> IPv6 - enabled network interfaces usually have more than one IPv6 address, for example, a link - local and a global address, and permanent versus temporary addresses . IPv6 introduces the concepts of address scope and selection preference, yielding multiple choices for source and destination address selections in communication with another host . </P> <P> The preference selection algorithm, which selects the most appropriate address to use in communications with a particular destination (including the use of IPv4 - mapped addresses in dual - stack implementations), is based on a user - customizable preference table that associates each routing prefix with a precedence level . The default table is as follows: </P> <Dl> <Dd> <Table> <Tr> <Th> Prefix </Th> <Th> Precedence </Th> <Th> Label </Th> <Th> Usage </Th> </Tr> <Tr> <Td>:: 1 / 128 </Td> <Td> 50 </Td> <Td> 0 </Td> <Td> Localhost </Td> </Tr> <Tr> <Td>:: / 0 </Td> <Td> 40 </Td> <Td> </Td> <Td> Default unicast </Td> </Tr> <Tr> <Td>:: ffff: 0: 0 / 96 </Td> <Td> 35 </Td> <Td> </Td> <Td> IPv4 - mapped IPv6 address </Td> </Tr> <Tr> <Td> 2002:: / 16 </Td> <Td> 30 </Td> <Td> </Td> <Td> 6to4 </Td> </Tr> <Tr> <Td> 2001:: / 32 </Td> <Td> 5 </Td> <Td> 5 </Td> <Td> Teredo tunneling </Td> </Tr> <Tr> <Td> fc00:: / 7 </Td> <Td> </Td> <Td> 13 </Td> <Td> Unique local address </Td> </Tr> <Tr> <Td>:: / 96 </Td> <Td> </Td> <Td> </Td> <Td> IPv4 - compatible addresses (deprecated) </Td> </Tr> <Tr> <Td> fec0:: / 10 </Td> <Td> </Td> <Td> 11 </Td> <Td> Site - local address (deprecated) </Td> </Tr> <Tr> <Td> 3ffe:: / 16 </Td> <Td> </Td> <Td> 12 </Td> <Td> 6bone (returned) </Td> </Tr> </Table> </Dd> </Dl> <Dd> <Table> <Tr> <Th> Prefix </Th> <Th> Precedence </Th> <Th> Label </Th> <Th> Usage </Th> </Tr> <Tr> <Td>:: 1 / 128 </Td> <Td> 50 </Td> <Td> 0 </Td> <Td> Localhost </Td> </Tr> <Tr> <Td>:: / 0 </Td> <Td> 40 </Td> <Td> </Td> <Td> Default unicast </Td> </Tr> <Tr> <Td>:: ffff: 0: 0 / 96 </Td> <Td> 35 </Td> <Td> </Td> <Td> IPv4 - mapped IPv6 address </Td> </Tr> <Tr> <Td> 2002:: / 16 </Td> <Td> 30 </Td> <Td> </Td> <Td> 6to4 </Td> </Tr> <Tr> <Td> 2001:: / 32 </Td> <Td> 5 </Td> <Td> 5 </Td> <Td> Teredo tunneling </Td> </Tr> <Tr> <Td> fc00:: / 7 </Td> <Td> </Td> <Td> 13 </Td> <Td> Unique local address </Td> </Tr> <Tr> <Td>:: / 96 </Td> <Td> </Td> <Td> </Td> <Td> IPv4 - compatible addresses (deprecated) </Td> </Tr> <Tr> <Td> fec0:: / 10 </Td> <Td> </Td> <Td> 11 </Td> <Td> Site - local address (deprecated) </Td> </Tr> <Tr> <Td> 3ffe:: / 16 </Td> <Td> </Td> <Td> 12 </Td> <Td> 6bone (returned) </Td> </Tr> </Table> </Dd>

Ipv6 does not use which type of address