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A Solicited-Node multicast address is an IPv6 multicast address valid within the local-link (e.g. an Ethernet segment or a Frame Relay cloud). Every IPv6 host will have at least one such address per interface. Solicited-Node multicast addresses are used in Neighbor Discovery Protocol for obtaining the layer 2 link-layer addresses of other nodes.〔RFC 2461 Neighbor Discovery for IP Version 6 (IPv6)〕 A Solicited-Node multicast address is created by taking the last 24 bits of a unicast or anycast address and appending them to the prefix ff02::1:ff00:0/104.〔RFC 4291 IP Version 6 Addressing Architecture〕 It is important to realize that we have taken 104 bits from the address, so that the last byte of the penultimate field 00 is not used in the prefix. Look at the examples below where the last 24 bits of the multicast address begin after ff. A host is required to join a Solicited-Node multicast group for each of its configured unicast or anycast addresses. Example: If we have an interface with the IP address fe80::2aa:ff:fe28:9c5a the associated Solicited-Node multicast address is ff02::1:ff28:9c5a. So we must join to the multicast group represented by this address. == Working Example == Assume a host needs to make a local delivery to another host on the local network, and the target host has an IPv6 address of fe80::2aa:ff:fe28:9c5a (as in Example 2 above). In order to make a Layer-2 (e.g. Ethernet) delivery, it needs to know the target host's hardware address (e.g. "Ethernet MAC address"). But in order to do this, it must first determine which hardware address to send it to. To do this, an IPv6 host will construct the Solicited-node Multicast Address related to the target address. We can see this clearly if we look at an example using the equivalent uncompressed IPv6 address.
The result of this process is the IPv6 link-local solicited node multicast address that the Neighbor Solicitation packet is sent to. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Solicited-node multicast address」の詳細全文を読む スポンサード リンク
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