A multilayer switch is designed to perform routing functions as well as switching, which allows it to efficiently manage and aggregate traffic from access switches before it proceeds to the core network layer. This capability optimizes performance by performing routing between VLANs at high speeds and reduces the burden on the core layer. In contrast, an unmanaged switch cannot provide any layer 3 functionality or intelligent traffic management. A firewall, while important for security, is not primarily used for traffic aggregation in a network's architecture. An access point provides wireless connectivity to devices and does not serve the purpose of aggregating traffic from multiple switches.