Layer 2 Switches

Layer 2 switching is hardware based, which means it uses the media access control address (MAC address) from the host's network interface cards (NICs) to decide where to forward frames. Switches use application-specific integrated circuit (ASICs) to build and maintain filter tables (also known as MAC address tables). One way to think of a layer 2 switch is as a multiport bridge.Layer 2 switching is highly efficient because there is no modification to the data packet, only to the frame encapsulation of the packet, and only when the data packet is passing through dissimilar media (such as from Ethernet to FDDI). Layer 2 switching is used for workgroup connectivity and network segmentation.