Enhanced random early detection algorithm BACnet router for congestion avoidance

This paper analyses the reason for congestion in BACnet network and conventional congestion avoidance algorithm. On the base of conventional RED algorithm, an absolute priority based congestion avoidance algorithm named enhanced random early detection (ERED) algorithm is presented. Similar to the conventional RED algorithm, ERED detects congestion according to the average queue length. ERED differs from conventional RED algorithm in queue management and dropping strategy. ERED adopts active queue management mechanism to store packets. ERED drops packets according to priority. Combined with BACnet standard's congestion control mechanism, ERED can be used by BACnet router to solve the congestion in BACnet network. At the same time, ERED algorithm ensures the reliability of BACnet network