Using only proportional jitter scheduling at the boundary of a Differentiated Service network: simple and efficient

There exist some studies in proportional delay scheduling algorithms for a Differentiated Service (DiffServ) network which schedule the packets between different classes proportionally based on queuing delay. Traditionally, it is necessary to implement such proportional delay scheduling algorithms at all the routers of the network for receiving proportional delay between different classes. In this paper, we propose a new and simple model, which does not provide proportional delay but delay jitter between different classes. In addition, we point out that for receiving proportional jitter in such a DiffServ Network, it is only necessary to implement a proportional jitter scheduling algorithm at the boundary of the network. Furthermore, we propose some networks using RJPS (relative jitter packet scheduling) and WTP (waiting time priority) at different positions (core or egress) and a playout buffer delay adjustment algorithm (Concord algorithm) at the receiver. Finally we compare its performance in terms of normalized end-to-end delay with different loss probabilities at the playout buffer. Our first result showed that a proportional jitter DiffServ network achieves better performance while keeping the cost of implementation lower in some cases.