ATM-GFR Buffer Management and Scheduling Issues: A Performance Study Using TCP

We overview in this paper the buffer management and scheduling issues and draw upon published work to illustrate the possible alternatives of GFR implementation. Performance evaluation has also been done on ATM-GFR’s buffer management algorithms and scheduling algorithms. The simulation results have shown that two-static-threshold-buffermanagement and per-VC-buffer management give the best performance comparing with plain UBR, UBR-EPD and per-VC scheduling. We have also found that the two-threshold buffer management scheme is significant to handle CLP0+1 traffic. This scheme can distinguish between the tagged (low priority) and untagged (high priority) packets of the traffic and protect the bandwidth from flushing by tagged packets. The per-VC scheduling without the sensitivity of tagged/untagged frames can lead to the poor performance for untagged (high priority) packets.