Certified Information Systems Security Professional (CISSP) Practice Exam

A switch primarily operates at Layer 2 of the OSI model, which is the Data Link layer. At this layer, the switch is responsible for forwarding data frames between devices on the same local area network (LAN). It uses MAC addresses to determine the destination of these frames, facilitating efficient communication and reducing network collisions.

While routers operate at Layer 3 (the Network layer) and handle IP addresses for inter-network communication, and firewalls can operate at various layers depending on their design, they do not primarily function at Layer 2. Hubs, although considered Layer 1 devices (Physical layer), do not have the intelligent forwarding capabilities of switches, as they simply broadcast all incoming traffic to all ports without considering the destination MAC addresses. Thus, the specific role and functionality of a switch in processing data based on MAC addresses and managing traffic at the Data Link layer confirm its primary operation at Layer 2 of the OSI model.