Which layer of the network model is commonly described as the high-speed backbone?

• A. Access Layer
• B. Distribution Layer
• C. Core Layer
• D. Physical Layer

Answer: (C)

In many enterprise networks, traffic needs to move quickly between different parts of the network, and the layer that provides this high-speed backbone is the core layer. It sits at the center of the design, interconnecting distribution-layer devices and offering very high bandwidth, low latency, and redundancy. The core is optimized for fast forwarding with minimal processing, so it can carry large volumes of traffic across the network fabric without becoming a bottleneck. End-user access and policy enforcement are handled at the other layers—access for user devices and distribution for inter-VLAN routing and policy—while the physical layer deals with cables and signaling rather than backbone transport.