Simulation-based performance evaluation of queuing for e-learning real time system

Abstract

Electronic learning has produced a comfortable, sophisticated, interactive and adaptable teaching model. Moreover, the consistent technical progress in this field allows the development of increasingly interesting applications [1]. We chose to select those elements to create an e-learning environment. This paper presents a model of the multi-tiered e-learning system based on Web Services. It shows architecture for implementing e-learning environment by taking into account quality of service (QoS) requirements namely traffic dropped, traffic received and packet end to end delay. However, there exists no known simulation approach on how to deploy a popular real-time network service such as e-learning system. This paper offers remarkable details on how to model and configure OPNET for such a purpose. The study has been carried out using OPNET IT Guru on 3 scenarios are suggested first before enabling any QoS mechanism at the routers, second apply class based weighted fair queuing using low latency queue (CBWFQ-LLQ) for video traffic and last scenario apply CBWFQ-LLQ for voice. The simulation results show that CBWFQ with LLQ for Voice Traffic has a superior quality than the other techniques. This model was tested with different number of learners. Results indicate that improvements caused by traffic differentiation, become more significant as the number of users increases.