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.