Avoiding bufferbloat with frame-drop threshold notification in ring aggregation networks

In recent years, cost reduction and capacity enlargement of memories have resulted in more and more buffers in switches and routers. Consequently, today's network suffers from bufferbloat, in which excess frame buffering causes high latency and jitter and reduces throughput. N rate N+1 color marking (NRN+1CM) was proposed to achieve per-flow fairness in a ring aggregation network. With NRN+1CM, colors are assigned to frames based on input rate and frames are discarded based on their color and frame-drop threshold. Although bufferbloat is avoided by its frame-drop threshold notification process, it was not clarified with a queuing model. This paper demonstrates how bufferbloat is avoided using M(n)/M/1/K queuing model and the formulated model is verified with a computer simulation.