Bufferbloat: Dark Buffers in the Internet Networks without effective AQM may again be vulnerable to congestion collapse.

Today’s networks are suffering from unnecessary latency and poor system performance. The culprit is bufferbloat, which is the existence of excessively large and frequently full buffers inside the network. Large buffers have been inserted all over the Internet without sufficient thought or testing. They damage or defeat the fundamental congestion-avoidance algorithms of the Internet’s most common transport protocol. Long delays from bufferbloat are frequently attributed incorrectly to network congestion, and this misinterpretation of the problem leads to the wrong solutions being proposed. Congestion is an old problem on the Internet, appearing in various forms with different symptoms and causing major problems. Buffers are essential to the proper functioning of packet networks, but overly large, unmanaged, and uncoordinated buffers create excessive delays that frustrate and baffle end users. Many of the issues that create delay are not new, but their collective impact has not been widely understood. Thus, buffering problems have been accumulating for more than a decade. We strive to present these problems with their impacts so that the community can understand and act upon the problem and, we hope, learn to prevent future problems. This article does not claim to be the first to identify the problems of excessive buffering, but it i