  Weaknesses in several recently proposed ideas about congestion control and
avoidance in high-speed netwroks are identified. Both sides of the debate
concerning prior reservation of resources versus walk-in service, open-loop
control versus feedback control, rate control versus window control, and
router-based control versus source-based control are presented. The
circumstances under which backpressure is useful or not are discussed, and it
is argued that a single congestion scheme is not sufficient, but that a
combination of several schemes is required for complete congestion management
in a network.
