What is the role of a Layer 2 switch?

A Layer 2 switch primarily operates at the data link layer of the OSI model, which is responsible for the transfer of data frames between devices within the same local area network (LAN). The main function of a Layer 2 switch is to analyze the MAC (Media Access Control) addresses contained in the frames it receives. By doing this, it can make decisions on how to forward these frames to their respective destinations.

When a switch receives a frame, it checks its MAC address table to determine the appropriate port to use for forwarding. If the destination MAC address is found in this table, the switch sends the frame out on the specified port. If the address is not found, the switch floods the frame to all ports except the one it originated from, ensuring that it reaches its destination as efficiently as possible.

This capability to forward frames based on MAC addresses enables Layer 2 switches to maintain high network efficiency by reducing unnecessary traffic on the network and ensuring effective communication between devices.