Nonlinear AQM for Multiple RED Routers

The existing RED algorithms act on subscribers and edge routers only, and the link capacities between edge routers and connected core routers have not been considered. When core router in a two layers´ network experiences congestion, the connected edge routers have no ability to response their access data rates. Thus, it is difficult to achieve the congestion control for the large scale network with many edge routers and core routers. To solve the problems, we propose two multiple RED routers algorithms of congestion control for two layers´ network. One RED algorithm implements fair link capacities of edge routers, and the other one implements unequal link capacities of edge routers, but require the core routers to have multi-queues buffers and multiple RED to support. The proposed algorithms achieve the network congestion control by operating RED parameters on the conditions of proposed three theorems for core and edge routers. The dynamic simulation results verify the proposed control algorithms for core and edge routers to be valid.