Fairness of scheduling algorithms for real-time traffic in DiffServ based networks

This paper presents methodology of provisioning QoS (Quality of Service) in DiffServ based IP network. DiffServ is scalable IP based technology which can efficiently provide QoS in networks of DiffServ supporting routers. We evaluated performances of our proposed scheme for QoS provisioning of real-time traffic, using WFQ (Weighted Fair Queuing) scheduler to schedule the transmissions. Simulations are performed using network simulator ns2, while EXP and CBR traffic generators are used as real-time traffic sources for voice and video applications. Through the simulation study we show the effect on queuing delays and jitter of both traffic types when their WFQ weights vary and derive and optimal weights that provide the best overall delay and jitter for real-time traffic.