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

Page 105

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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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