One embodiment disclosed relates to a method of routing a packet by way of a router aggregation. A packet is received from outside the aggregation by an initially receiving router/switch unit. Router functions are performed by the initially receiving router unit, including modification of the packet. The packet is then sent to a layer 2 network of the aggregation, wherein switching functions are performed on the packet. Another embodiment disclosed relates to a cooperative aggregation of router/switch units. The aggregation includes a plurality of the router/switch units, and a switching network interconnecting the units. The cooperative aggregation functions as a single router from a perspective of an external network device coupled to the system.