• Journal of KIISE:Information Networking
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• v.29 no.4
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• pp.375-385
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• 2002

The IETF has defined the Intserv model and the RSVP signaling protocol to improve QoS capability for a set of newly emerging services including voice and video streams that require high transmission bandwidth and low delay. However, since the current Intserv model requires each router to maintain the states of each service flow, the complexity and the overhead for processing packets in each rioter drastically increase as the size of the network increases, giving rise to the scalability problem. This motivates our work; namely, we investigate and devise new control schemes to enhance the scalability of the Intesev model. To do this, we basically resort to the SCORE network model, extend it to fairly well adapt to the three services presented in the Intserv model, and devise schemes of the QoS scheduling, the admission control, and the edge and core node architectures. We also carry out the computer simulation by using ns-2 simulator to examine the performance of the proposed scheme in respects of the bandwidth allocation capability, the packet delay, and the packet delay variation. The results show that the proposed scheme meets the QoS requirements of the respective three services of Intserv model, thus we conclude that the proposed scheme enhances the scalability, while keeping the efficiency of the current Intserv model.

• Journal of the Korea Society of Computer and Information
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• v.14 no.3
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• pp.121-131
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• 2009

BcN provides a wide variety of high-quality multimedia services such as broadcasting and communication convergence services. But the quality degeneration is observed in BcN when we use broadcasting and communication convergence service via more than one network of different internet service providers. In this paper, a QoS management system which is able to measure and maintain objectively the quality-related information in overall networks is proposed. The proposed QoS management system is tested on the pilot networks of BcN consortiums by measuring the quality of voice and video experienced by the actual users of the commercial video phone services. The result of the experiment shows that it is possible to figure out service qualify between a user and a service provider by analyzing the information from agents. The per-service traffic information collected by probes is proved to be useful to pinpoint the party responsible for the loss of the service qualify in case of the services including different service providers. As the result of the experiment, it is shown that the proposed QoS management system would play a key role of resolving the quality dispute, which is one of the important issues of QoS-guaranteed BcN.