Where is the aggregation switch connected

An aggregation switch is connected between access switches and core switches, consolidating traffic from multiple edge devices before forwarding it to the network core.

Connectivity Overview

An aggregation switch serves as an intermediate layer in a network, often referred to as the distribution or aggregation layer. It is physically connected to all access switches in its domain, which may include wired access switches, wireless access points, or other edge devices, and it forwards traffic upstream to the core switches or routers for high-speed backbone connectivity . This setup allows the aggregation switch to consolidate multiple lower-speed connections into a higher-bandwidth uplink, improving network efficiency and reducing bottlenecks .

Redundancy and High Availability

Aggregation switches are typically deployed in pairs to provide resiliency. Each switch in the pair can connect to the same set of access switches and to the core, often using link aggregation protocols like LACP to combine multiple physical links into a single logical connection . This ensures failover capability if one link or switch fails, maintaining uninterrupted network service .

Connection to Servers and Data Center Services

In larger networks or data centers, aggregation switches may also connect dual-attached servers, storage devices, and other network-based services. These connections are usually high-speed (10/25/40/100 GbE) to handle large volumes of traffic efficiently . However, end-user devices like laptops, IP phones, or wireless access points are generally not connected directly to the aggregation layer .

Summary of Connections

• Downstream: All access switches and edge devices in the network.
• Upstream: Core switches or routers for high-speed backbone connectivity.
• Optional: Dual-attached servers, storage, and data center services.
• Redundancy: Paired aggregation switches with link aggregation for failover and load balancing.

This hierarchical design ensures scalability, reliability, and simplified network management, making the aggregation switch a critical component in enterprise, campus, and data center networks .