Why do switches help reduce sniffing?

Why do switches help reduce sniffing?

• A. They broadcast to all ports
• B. They operate slower
• C. They send packets only to the originating computer port
• D. They remove the need for encryption

Answer: (C)

Switches reduce sniffing by keeping traffic confined to the specific device it’s meant for. They learn which MAC addresses are reachable through each port and build a forwarding table. When a frame arrives, the switch forwards it only to the port where the destination device is connected, rather than blasting it to every connected port. This means other devices on the network won’t see those frames, making packet sniffing much harder. If the destination isn’t known yet, the switch floods to all ports except the incoming one, but once it learns the mapping, traffic stays isolated to the correct port. By contrast, what would happen on a hub is that every frame is repeated to all ports, which enables sniffing. The other options aren’t about how switching confines traffic, and encryption isn’t affected by switching behavior.

Switches reduce sniffing by keeping traffic confined to the specific device it’s meant for. They learn which MAC addresses are reachable through each port and build a forwarding table. When a frame arrives, the switch forwards it only to the port where the destination device is connected, rather than blasting it to every connected port. This means other devices on the network won’t see those frames, making packet sniffing much harder. If the destination isn’t known yet, the switch floods to all ports except the incoming one, but once it learns the mapping, traffic stays isolated to the correct port. By contrast, what would happen on a hub is that every frame is repeated to all ports, which enables sniffing. The other options aren’t about how switching confines traffic, and encryption isn’t affected by switching behavior.