Layer 2 and Layer 3 refer to different parts of IT network communications. The ‘layers’ refer to how you configure an IT network, and the standard for network communications called the Open System Interconnection (OSI) model.

Layer 2 is a broadcast Media Access Control (MAC) level network, while Layer 3 is a segmented routing over internet protocol (IP) network.

OSI is a networking model comprised of seven ‘layers’. It’s a controlled hierarchy where information is passed from one layer to the next creating a blueprint for engineers to organize communication.

Layer 2 is the data link where data packets are encoded and decoded into bits. The MAC sub layer controls how a computer on the network gains access to the data and permission to transmit it and the LLC (Logical Link control) layer controls frame synchronization, flow control and error checking.

Layer 3 provides switching and routing technologies, creating logical paths, known as virtual circuits, for transmitting data from node to node. Routing and forwarding are functions of this layer, as well as addressing, internetworking, error handling, congestion control and packet sequencing.