What does a switch use to determine where to send incoming frames?

A switch uses a MAC address table to determine where to send incoming frames. This table maintains a mapping between MAC addresses and the switch ports to which they are connected. When a frame arrives at the switch, it examines the source MAC address and updates its MAC address table if the address is not already present, associating it with the port through which the frame was received.

For outgoing frames, the switch checks the destination MAC address against its MAC address table. If it finds a matching entry, it sends the frame to the corresponding port. If the MAC address is not found in the table, the switch will broadcast the frame to all ports except the one it was received on, allowing the destination device to respond and thus update the MAC address table.

This process ensures that frames are delivered efficiently to their intended recipients, minimizing unnecessary traffic on the network. The other concepts listed, such as IP address tables and routing tables, are more relevant to routers and Layer 3 devices, while ARP caches are used to resolve IP addresses to MAC addresses rather than directing frames within a switch.