What Is Layer 2?
Layer 2 is a type of networking protocol that operates at the data link layer, which is the second layer in the OSI model. It provides an interface between physical network devices and higher-level protocols such as IP. Layer 2 networks are used to connect computers on local area networks (LANs) or wide area networks (WANs). The most common types of Layer 2 protocols include Ethernet, Token Ring, FDDI, ATM and Frame Relay.
Layer 2 switches are responsible for forwarding packets based on their MAC addresses. They use a process called address learning to build up a table of MAC addresses associated with each port on the switch. When a packet arrives at one port, it looks up its destination address in this table and forwards it out another port if necessary. This allows for efficient communication within LANs by reducing broadcast traffic and allowing multiple hosts to communicate directly without having to go through routers or other intermediate devices.