QoS adaptation in real time systems based on CBWFQ

The evolution of the World Wide Web (WWW) service has incorporated new distributed multimedia conference applications, powering a new generation of e-services development, and allowing improved interactivity. Most common interactive real-time applications are fault-tolerant but suffer from QoS limitations; low-latency requirements and reliability are cumulative to conference success, it may easily absorb all network resources and the subjective quality sensed by users would remain poor if the available resources are used indiscriminately. This paper simulates a network infrastructure design that classifies and prioritizes the real-time traffic in order to improve the performance of the real-time applications, taking into consideration of the performance of non real-time applications. This infrastructure has been designed to present a typical network of a university campus, so that in this way it can be implemented in any campus. In this paper 3 scenarios are suggested first before enabling any QoS mechanism at the routers, second use class based weighted fair queuing using low latency queue (CBWFQ-LLQ) for video traffic and last scenario apply CBWFQ-LLQ for voice. The simulation is conducted using OPNET IT Guru. Simulation results demonstrated that applying LLQ for voice improves the performance of overall real-time and non real-time application.