Layer 1: Physical Layer Data : Physical bits Equipment : cables, fiber optic, ethernet hubs Layer 2 Data Link 2A. MAC ( Medium Access control) 2B. LLC ( Logical Link Control) Data : Frames Equipment : Switches , Bridges , Network Card. Layer 3 : Network Layer Data : packet Equipment: Firewalls L2 Switch (hardware) … Continue reading L1, L2 ,L3 equipment and L3 vs L4 switches