Toronto Networking Seminar

A Measurement-Based Call Admission Control Strategy for VoIP in the DiffServ Environment

John Daigle
University of Mississippi

Date:  Friday, November 3,  11am
Location: BA 2165 (Bahen Center)


We propose and analyze a simple measurement-based call admission control procedure for carrying VoIP in a DiffServ environment.  We assume voice sources are leaky-bucket controlled with known leaky-bucket parameters.  We analyze the leaky bucket to derive the distribution of the time over which voice sources generate traffic at peak rate.  We then use the results of that analysis, which provides complete knowledge of the traffic generation characteristics of a single source, to derive a Markov chain model that characterizes the voice packet generation process of a single voice source.  We then derive a simple stateless threshold policy for admission control.  We then show, via simulation, that the QoS achieved using the threshold-based CAC policy is very close to that achieve by a stateful admission control policy even at very high traffic utilization.


John N. Daigle is Director, Center for Wireless Communications, and Professor of Electrical Engineering at the University of Mississippi, Oxford. He received a doctorate from Columbia University in operations research. Prof. Daigle is a Fellow of the IEEE. He has served as Editor-in-Chief of IEEE Network and IEEE Communication Surveys and Tutorials, and was formerly an Editor for IEEE/ACM Transactions on Networking and an Associate Editor of Operations Research. He was formerly Director of Education of the IEEE Communications Society and has previously served on that society's Board of Governors. He is a past chairman of the Society's Technical Committee on Computer Communications, and he has served on the technical program committees of numerous IEEE conferences and workshops. Prof. Daigle has received the 2004 TCCC Outstanding Service Award form the IEEE Communication Society's Technical Committee on Computer Communications.