IPv6 address types
This information shows the categories of different IPv6 address types, and explains the uses for each of them.
IPv6 addresses are categorized into these basic types:
- Unicast address
- The unicast address specifies a single interface. A packet sent to a unicast
address destination travels from one host to the destination host.The two regular types of unicast addresses include:
- Link-local address
- Link-local addresses are designed for use on a single local link (local
network). Link-local addresses are automatically configured on all interfaces.
The prefix used for a link-local address is
fe80::/10. Routers do not forward packets with a destination or source address containing a link-local address. - Global address
- Global addresses are designed for use on any network. The prefix used
for a global address begins with binary
001.
There are two special unicast addresses defined:- Unspecified address
- The unspecified address is
0:0:0:0:0:0:0:0. You can abbreviate the address with two colons (::). The unspecified address indicates the absence of an address, and it can never be assigned to a host. It can be used by an IPv6 host that does not yet have an address assigned to it. For example, when the host sends a packet to discover if an address is used by another node, the host uses the unspecified address as its source address. - Loopback address
- The loopback address is
0:0:0:0:0:0:0:1. You can abbreviate the address as::1. The loopback address is used by a node to send a packet to itself.
- Anycast address
- An anycast address specifies a set of interfaces, possibly at different locations, that all share a single address. A packet sent to an anycast address goes only to the nearest member of the anycast group. IBM® i can send to anycast addresses, but cannot be a member of an anycast group.
- Multicast address
- The multicast address specifies a set of interfaces, possibly
at multiple locations. The prefix used for a multicast address is
ff. If a packet is sent to a multicast address, one copy of the packet is delivered to each member of the group. The IBM i operating system currently provides basic support for multicast addressing.