Scalable Router Memory Architecture Based on Inter-leaved DRAM: Analysis and Numerical Studies

Routers need buffers to store and forward packets, especially when there is network congestion. With current memory technology, neither the SRAM nor the DRAM alone is suitable for high-speed Internet routers that require both large capacity and fast access time. Some previous work has been carried out to combine the two technologies together and made a hybrid memory system [S. Iyer et al., 2001]. In this paper, we base the router memory on the interleaved DRAM architecture and propose an efficient memory management algorithm (CM-MMA) for it. The main advantage of the CM-MMA is that it can scale to a very large capacity while only employing small enough SRAM to guarantee a fast access time. The CM-MMA is also more responsive to traffic than previously proposed solutions, especially in light traffic situations. We perform both analysis and numerical studies to the CM-MMA. We also show simulation results that conform to them very well.