2 C] Explain addressing strategies in IoT.
The first three blocks are designated as the global prefix, which is globally unique. The next block is designated as the subnet prefix, which identifies the subnet of an interface/gateway through which LANs may be connected to the Internet. Finally, the last four blocks (64 bits) of hexadecimal addresses are collectively known as the interface identifier (IID). IIDs may be generated based on MAC (media access control) identifiers of devices/nodes or using pseudo-random number generator algorithms.
The IPv6 addresses can be divided into seven separate address types, which is generally based on how these addresses are used or where they are deployed.
- Global Unicast (GUA): These addresses are assigned to single IoT entities/ interfaces; they enable the entities to transmit traffic to and from the Internet In regular IoT deployments, these addresses are assigned to gateways, proxies, or WANs.
- Multicast: These addresses enable transmission of messages from a single networked entity to multiple destination entities simultaneously.
- Link Local (LL): The operational domain of these addresses are valid only within a network segment such as LAN. These addresses may be repeated in other network segments/LANs, but are unique within that single network segment
- Unique Local (ULA): Similar to LL addresses, ULA cannot be routed over the Internet. These addresses may be repeated in other network segments/LANS but are unique within that single network segment.
- Loopback: It is also known as the localhost address. Typically, these addresses are used by developers and network testers for diagnostics and system checks.
- Unspecified: Here, all the bits in the IPv6 address are set to zero and the destination address is not specified.
- Solicited-node Multicast: It is a multicast address based on the IPv6 address of an IoT node or entity.