ICMPv6 message
Function
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.
z
The 3com switch 4500 does not support the RS, RA, or Redirect message.
z
Of the above mentioned IPv6 NDP functions, 3com switches 4500 support the following three
functions: address resolution, neighbor unreachability detection, and duplicate address detection.
The subsequent sections present a detailed description of these three functions and relevant
configuration.
The NDP mainly provides the following functions:
Address resolution
Similar to the ARP function in IPv4, a node acquires the link-layer address of neighbor nodes on the
same link through NS and NA messages.
Figure 68-3
shows how node A acquires the link-layer
address of node B.
Figure 68-3
Address resolution
The address resolution procedure is as follows:
68-6
