The access layer consists of layer 3 switches, which take routed and switched data packets from the distribution switches and then route them to the access devices in subnets. The access devices in subnets can be modems, video display units, receiver audio phones, IP-based. Layer 2 switches (L2 switches) use physical network addresses. Physical addresses, also known as link-layer, hardware, or MAC-layer addresses, identify individual devices. Most hardware devices are permanently assigned this number during the manufacturing process. Without them, the Internet as we know it today would not exist. It especially utilizes MAC addresses to direct information packets between devices that are on the exact same network.