Improving RED algorithm performance in ATM networks

Supporting TCP data traffic over ATM-UBR service class requires special mechanisms to improve throughput and fairness while minimizing delay. Several ATM buffer management schemes have been proposed to improve throughput and fairness for a Selective Drop: Early Packet Discard (EPD) and Fair Buffer Allocation (FBA). Concurrently RED (Random Early Detection) algorithm proposed for packet networks (including IP) avoids, by the mean of packet marking, the global synchronization of TCP sources while maintaining high throughput and low delay. In this paper we study the adaptation of RED algorithm to ATM (using EPD) and introduce an algorithm to improve its fairness. We propose and compare a cell based and a packet based RED algorithm. Finally we compare performances of RED with EPD and pure EPD, in terms of throughput, fairness and delay, in the presence of a background ON/OFF source.