Pro-active QoS scheduling algorithms for real-time multimedia applications in communication system

This paper studies the performance of the OccuPancy Adjusting (OCP A) dynamic QoS scheduling algorithm and two newly proposed dynamic QoS scheduling algorithm, known as the dynamic QoS scheduling algorithm with delay estimation and the hybrid dynamic QoS scheduling algorithm. The newly designed algorithms are intended to reduce the propagated delay caused by transient packets that will eventually be dropped due to expired delay. The essence of these new algorithms is to apply a pro-active approach in accessing the admission of packets into the buffer, which is based on the estimated delay that is likely to be experienced by the respective packets. The estimation algorithm is driven by a recursive calculation of the estimated delay, which is influenced by the buffer occupancy. The results obtained through the simulation model have indicated that the two newly proposed algorithms are able to improve the average delay, buffer requirements and packet loss ratio for delay sensitive traffic, as compared to the OCP A algorithm.