Configure Two-Tier core switches as a VSX pair for Layer 2 aggregation of the data center access switches, IP data center services, and routing to the main campus. What Is an Aggregation Switch and How to Choose? The three layers of a traditional three-layer network design are the core layer, aggregation layer, and access layer. Rather than implementing a flat network, this model endorses a hierarchical structure, which is generally easier to manage and troubleshoot. It facilitates the connectivity because it would rapidly become impractical to. An 8-port, Layer 2 switch made for 10G SFP+ connections. High-performance 10G SFP modules for optimal connectivity.