Core-Stateless Fair Queueing

This paper addresses some of the issues from the previous paper about the scalability and complexity of the fair queuing algorithm. The author proposes using an island of routers, having the edge maintaining the basic flow state, while the middle routers (core routers) don't need to maintain state, and they simply use a probabilistic drop packet algorithm and a FIFO queue.

The results after testing showed that they achieved a significant degree of fairness. Although this can't compare to a real fairness queuing algorithm, they argue that it's "good enough" and also cost effective and scales well. It also out performs several other queuing algorithms in terms of fairness. It seems somewhat related to the idea of landmark routing, where instead of being fair at each node, dedicate some nodes to monitor the fairness while the other core nodes save computation and power by a simpler FIFO queue.

It's always interesting to see a proposed algorithm that doesn't perform as well as a previous one, but is "good enough" and cost effective. The author claims exactly that for this algorithm. The two papers together both agree that routing is a big aspect of flow control now, but it seems the proposals focused on different tradeoffs, with the FQ being focused on fairness of bandwidth etc, while this paper focuses on the scalability and complexity efficiency.