Introduction To Ipv6 Neighbor Discovery Protocol - H3C S3100 8C SI Operation Manual

Operation Manual – IPv6 Management
H3C S3100 Series Ethernet Switches

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:
Address resolution
Neighbor unreachability detection
Duplicate address detection
Router/prefix discovery
Address autoconfiguration
Redirection
Table 1-3
Table 1-3 Types and functions of ICMPv6 messages
ICMPv6 message
Neighbor solicitation (NS)
message
Neighbor advertisement (NA)
message
Router solicitation (RS)
message
Router advertisement (RA)
message
Redirect message
lists the types and functions of ICMPv6 messages used by the NDP.
Function
Used to acquire the link-layer address of a
neighbor
Used to verify whether the neighbor is reachable
Used to perform a duplicate address detection
Used to respond to a neighbor solicitation message
When the link layer address changes, the local
node initiates a neighbor advertisement message
to notify neighbor nodes of the change.
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
With the RA message suppression disabled, the
router regularly sends a router advertisement
message containing information such as address
prefix and flag bits.
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.
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Chapter 1 IPv6 Configuration