Operation Manual – IPv6 Management
H3C S3100 Series Ethernet Switches
Chapter 1 IPv6 Configuration
1-7
1.1.3 Introduction to IPv6 Neighbor Discovery Protocol
The IPv6 neighbor discovery protocol (NDP) uses five types of ICMPv6 messages to
implement the following functions:
z
Address resolution
z
Neighbor unreachability detection
z
Duplicate address detection
z
Router/prefix discovery
z
Address autoconfiguration
z
Redirection
Table 1-3
lists the types and functions of ICMPv6 messages used by the NDP.
Table 1-3
Types and functions of ICMPv6 messages
ICMPv6 message
Function
Used to acquire the link-layer address of a
neighbor
Used to verify whether the neighbor is reachable
Neighbor solicitation (NS)
message
Used to perform a duplicate address detection
Used to respond to a neighbor solicitation message
Neighbor advertisement (NA)
message
When the link layer address changes, the local
node initiates a neighbor advertisement message
to notify neighbor nodes of the change.
Router solicitation (RS)
message
After started, a host sends a router solicitation
message to request the router for an address prefix
and other configuration information for the purpose
of autoconfiguration.
Used to respond to a router solicitation message
Router advertisement (RA)
message
With the RA message suppression disabled, the
router regularly sends a router advertisement
message containing information such as address
prefix and flag bits.
Redirect message
When a certain condition is satisfied, the default
gateway sends a redirect message to the source
host so that the host can reselect a correct next hop
router to forward packets.
