Weighted fair discard scheme for buffer management in the presence of network congestion

Abstract

Data discarding is widely used in networks as a mechanism for buffer management. It enables networks to satisfy various QoS requirements. In this paper, we propose a general weighted fair discard algorithm (WFD) for buffer management in the presence of network congestion and buffer overflow. WFD comprises two parts, discard weight and discard mechanism. Whenever there is a situation of buffer overflow, WFD removes some data from the buffer. The amount of data removed from individual connections is controlled by WFD and is proportional to connections' discard weights. Since discard weights can be flexibly assigned and dynamically adjusted, WFD can thus optimize the performance of various applications more efficiently, as compared with other discard disciplines, such as ‘drop tail’. In addition, certain interesting attributes of WFD are also analyzed in this paper, and results show that we can estimate possible data losses in advance and control them in realtime, as they are extremely useful for multi-streaming or adaptive applications.