The core switch has a three-layer structure as follows

A core switch operates at the core layer of a three-tier hierarchical network, connecting distribution switches and ensuring high-speed, reliable data transfer across the network.Core LayerThe core layer is the backbone of the network, where the core switch resides. It is designed for high-capacity, high-performance routing and switching, handling massive volumes of data with ultra-low latency and maximum throughput . Core switches provide Layer 3 functionality, enabling IP routing between VLANs, subnets, and security zones, and often include features like link aggregation, redundancy, and modular scalability . This layer ensures that data from multiple distribution switches is efficiently aggregated and forwarded across the network.Distribution LayerThe distribution layer acts as an intermediary between the core and access layers. It collects data from the access layer, performs selective routing and switching, and forwards traffic to the core layer . Layer 2 or Layer 3 switches in this layer help reduce congestion, enforce policies, and manage traffic efficiently. The distribution layer also provides redundancy and load balancing to maintain network reliability.Access LayerThe access layer is the point where end devices connect to the network. It includes switches that provide connectivity to computers, IP phones, cameras, and other devices . Access switches handle the initial routing and switching of data packets, which are then sent to the distribution layer for further processing. This layer ensures that users and devices can access network resources securely and efficiently.Summary of Data FlowAccess Layer: End devices send data to access switches.Distribution Layer: Data is aggregated, filtered, and routed toward the core.Core Layer: Core switches forward data at high speed across the network backbone, connecting multiple distribution switches and ensuring minimal latency . This three-layer hierarchical model provides scalability, simplified management, and improved performance, making it ideal for large enterprise networks and data centers .