11.1.5 Access, Distribution, and Core Layer Functions
The access layer is the network edge where traffic enters or exits. Its primary function is to provide user access and connect to the distribution layer. Modern access layer switches integrate intelligent services to enhance security, efficiency, and application performance.
The distribution layer connects the access and core layers, aggregating networks, managing routing boundaries, and enforcing network policies. It enhances reliability with redundancy and supports differentiated services for various applications.
The core layer is the network backbone. It connects several layers of the campus network. The core layer serves as the aggregator for all of the distribution layer devices and ties the campus together with the rest of the network. The primary purpose of the core layer is to provide fault isolation and high-speed backbone connectivity.
