In a local area network (LAN), the primary function of aswitch is to operate at Layer 2 (Data Link Layer) of the OSI model. Switches use MAC addresses to forward frames to the appropriate destination ports. This targeted forwarding mechanism divides the network into separate collision domains for each switch port. By isolating collision domains, switches significantly reduce the chance of collisions, enhancing the performance and efficiency of the network.

Unlike hubs, which forward all traffic to all ports (thus creating a single collision domain), switches intelligently forward only the necessary traffic to the correct port. This capability allows multiple simultaneous conversations on different switch ports without interference.

Routers, which operate at Layer 3 (Network Layer), are used to route packets between different networks, not within the same LAN. Wireless connectivity is provided by wireless access points (WAPs), not switches. Encryption is typically handled by security protocols or devices such as firewalls and not by switches directly.