Update on buffer sizing in internet routers

In the past two years, several papers have proposed rules that suggest two to five orders of magnitude reduction in Internet core router buffers. Others present scenarios where buffer sizes need to be significantly increased. So why the different rules? In this paper we briefly compare the different results and proposals, and summarize some recent preliminary experiments to validate the proposals. We'll see that different results apply to different parts of the network, and depend on several assumptions. For example, we believe that buffers can be safely reduced by an order of magnitude in the routers in service provider backbone networks; but it would be premature to reduce them in routers closer to the edge.