Question

"....For the following Solicited Node Multicast Address (SNMA)

1:FF:46:A702
...where does the 46:A702 part come from?"

Answer 1

The '46:A702' part of the Solicited Node Multicast Address '1:FF:46:A702' is extracted from the last 24 bits of a device's IPv6 unicast or anycast address to uniquely identify the destination node, reducing network congestion.

Step-by-step explanation:

The Solicited Node Multicast Address (SNMA) is an IPv6 address used for efficient network traffic management. When you refer to the SNMA 1:FF:46:A702, the 46:A702 portion is derived from the interface identifier of the target device's IPv6 address. In the IPv6 address structure, the last 24 bits of the solicited-node address are a direct copy from the last 24 bits of the corresponding unicast or anycast address. Here's how it works:

• The 'FF' in the SNMA indicates the address is a multicast address.
• The '1' represents the flags used in the multicast address. The exact value depends on the specific flags set.
• The '46:A702' portion comes from the actual IPv6 address that is being solicited. This helps in identifying the destination node without having to send the message to all nodes in the network.

The SNMA helps in reducing network congestion by ensuring that only the node that has the corresponding unicast or anycast address responds to a particular solicitation.