HPE 3100 Configuration Manual page 125

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Neighbor reachability detection
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Duplicate address detection
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Router/prefix discovery and address autoconfiguration
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Redirection
Table 7 ICMPv6 messages used by ND
ICMPv6 message
Neighbor Solicitation (NS)
message
Neighbor Advertisement
(NA) message
Router Solicitation (RS)
message
Router Advertisement (RA)
message
Redirect message
Address resolution
This function is similar to the ARP function in IPv4. An IPv6 node acquires the link-layer addresses of
neighboring nodes on the same link through NS and NA message exchanges.
Host A acquires the link-layer address of Host B on a single link.
Figure 53 Address resolution
The address resolution operates in the following steps:
1. Host A multicasts an NS message. The source address of the NS message is the IPv6 address
of the sending interface of Host A and the destination address is the solicited-node multicast
address of Host B. The NS message contains the link-layer address of Host A.
2. After receiving the NS message, Host B determines whether the destination address of the
packet is its solicited-node multicast address. If yes, Host B learns the link-layer address of
Host A, and then unicasts an NA message containing its link-layer address.
3. Host A acquires the link-layer address of Host B from the NA message.
Neighbor reachability detection
After Host A acquires the link-layer address of its neighbor Host B, Host A can use NS and NA
messages to check whether Host B is reachable.
Type Function
Acquires the link-layer address of a neighbor.
135 Verifies whether a neighbor is reachable.
Detects duplicate addresses.
Responds to an NS message.
136
Notifies the neighboring nodes of link layer changes.
Requests an address prefix and other configuration information for
133
autoconfiguration after startup.
Responds to an RS message.
134
Advertises information such as the Prefix Information options and
flag bits.
Informs the source host of a better next hop on the path to a
137
particular destination when certain conditions are satisfied.
115
Figure 53 shows how