Part I

In this article we describe recent work on buffer sizing for core Internet routers. This work suggests that the widely-used rule of thumb leads to buffers which are much larger than they need to be. For example, the buffer in a backbone router could be reduced from 1,000,000 packets to 10,000 without loss in performance. It could be reduced even further, perhaps to 10-20 packets, at the cost of a small amount of bandwidth utilization. This tradeoff is worth considering, for example for a possible future all-optical router.