Eui-64 address-based interface identifiers, Ipv6 neighbor discovery protocol – H3C Technologies H3C SecPath F1000-E User Manual

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Multicast addresses also include solicited-node addresses. A node uses a solicited-node multicast

address to acquire the link-layer address of a neighboring node on the same link and to detect duplicate

addresses. Each IPv6 unicast or anycast address has a corresponding solicited-node address. The format
of a solicited-node multicast address is:
FF02:0:0:0:0:1:FFXX:XXXX
Where FF02:0:0:0:0:1:FF is fixed and consists of 104 bits, and XX:XXXX is the last 24 bits of an IPv6

unicast address or anycast address.

EUI-64 address-based interface identifiers

An interface identifier is 64 bits and uniquely identifies an interface on a link.
Various types of interfaces generate EUI-64 address-based interface identifiers in different ways.

On an IEEE 802 interfaces (such as an Ethernet interface and a VLAN interface)

The interface identifier is derived from the link-layer address (typically a MAC address) of the interface.

To expand the 48-bit MAC address to a 64-bit interface identifier, the hexadecimal number FFFE (that is,

16 bits of 1111111111111110) is inserted into the MAC address (behind the 24th high-order bit). To ensure

that the obtained interface identifier is unique, the universal/local (U/L) bit (which is the seventh

high-order bit) is set to 1. Thus, an EUI-64 address-based interface identifier is obtained.

Figure 2

shows the process of how an EUI-64 address-based interface identifier is generated from a MAC

address.

Figure 2 Convert a MAC address into an EUI-64 address-based interface identifier

On a tunnel interface

The lower 32 bits of the EUI-64 address-based interface identifier are the source IPv4 address of the
tunnel interface. The higher 32 bits of the EUI-64 address-based interface identifier of an ISATAP tunnel

interface are 0000:5EFE, whereas those of other tunnel interfaces are all zeros. For more information

about tunnels, refer to Tunneling Configuration in the IP Services Volume.

On an interface of another type (such as a serial interface)

The EUI-64 address-based interface identifier is generated randomly by the device.

IPv6 Neighbor Discovery Protocol

The IPv6 Neighbor Discovery (ND) protocol uses five types of ICMPv6 messages to implement the

following functions:

Address resolution

Neighbor reachability detection

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