The paper presents an analysis in a DiffServ network scenario of the achievable QoS (Quality of Service) performance when different aggregation strategies between video and voice traffic flows are considered. Each network node of the analyzed DiffServ scenario is represented by a Worst-Case Fair Weighted Fair Queueing scheduler with a shaper obtained using a Shaped Starting Potential Fair Queueing. The system of each node, referred in literature as WF2Q+ scheduler, permits to guarantee the isolation among the different PHB (Per Hop Behavior) service classes, maintaining the multiplexing gain. The parameters setting of the WF2Q+ scheduler is also discussed. In particular, the necessary network resources, estimated by the WF2Q+ parameters setting obtained considering the aggregation of traffic sources belonging to the same service class, are compared with those estimated on a per flow basis. The higher gain achievable using the first approach with respect to the second one, is also qualitatively highlighted. The simulation results, presented in the paper, evidence the possible problems that can be raised when voice traffic is merged with video service traffic. As a consequence, the paper results suggest to consider in different service class queues the two kinds of traffic.
A Simulation Analysis of Aggregation Strategies in a WF2Q+Schedulers Network
GARROPPO, ROSARIO GIUSEPPE;GIORDANO, STEFANO;RUSSO, FRANCO
2001-01-01
Abstract
The paper presents an analysis in a DiffServ network scenario of the achievable QoS (Quality of Service) performance when different aggregation strategies between video and voice traffic flows are considered. Each network node of the analyzed DiffServ scenario is represented by a Worst-Case Fair Weighted Fair Queueing scheduler with a shaper obtained using a Shaped Starting Potential Fair Queueing. The system of each node, referred in literature as WF2Q+ scheduler, permits to guarantee the isolation among the different PHB (Per Hop Behavior) service classes, maintaining the multiplexing gain. The parameters setting of the WF2Q+ scheduler is also discussed. In particular, the necessary network resources, estimated by the WF2Q+ parameters setting obtained considering the aggregation of traffic sources belonging to the same service class, are compared with those estimated on a per flow basis. The higher gain achievable using the first approach with respect to the second one, is also qualitatively highlighted. The simulation results, presented in the paper, evidence the possible problems that can be raised when voice traffic is merged with video service traffic. As a consequence, the paper results suggest to consider in different service class queues the two kinds of traffic.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
