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講師略歴：
　　 David Lee(IEEE M'89-SM'91-F'96) was born in Hong Kong and grew up in Soozhow, China. He received a Master of Arts degree in Mathematics from Hunter College of City University of New York in 1982 and a Ph. D. degree in Computer Science from Columbia University in 1985. Since 1985 he has been with Bell Laboratories Research. He is Vice President of Bell Labs Research and the Director of Bell Laboratories Research, China. He has been an adjunct professor at Columbia University, Distinguished Guest Professor of Tsinghua University, a Visiting Faculty of National Institute of Standards and Technology, and a Visiting Professor of Institut National des Telecommunications, France. His current research interests are data networking, communication protocols and software, and complexity theory. David Lee is a Fellow of The IEEE and has the Bell Laboratories Research Distinguished Member of Technical Staff Award in 1996. David Lee is an editor of IEEE/ACM Transactions on Networking and an associate editor of Journal of Complexity.

講演概要：
　　This work has been motivated by the need to test interoperability of systems carrying voice calls over the IP network. Voice over IP (VoIP) systems must be integrated and interoperate with the existing Public Switched Telephone Network (PSTN) before they will be widely adopted. Standards have been developed to address this problem, but unfortunately different standards bodies and commercial consortiums have defined different standards. Furthermore, the prevailing commercial standard (H.323) is incomplete, complex, and presents the implementers with 'vendors latitudes''. As a result, there is no guarantee that the integrated VoIP systems would interoperate properly even if the implementations are all H.323-compliant.
　　Interoperability testing has become indispensable. We discuss criteria that cover all the required patterns of 'inter-operating behavior.'' We want to test all such system interoperations. On the other hand, test execution in real environment is expensive, and we want to minimize the number of tests while maintaining the coverage. We present a general method for automatic generation of test cases, which cover all the required system interoperations and contain a minimal number of tests. We study data structures and efficient test generation algorithms, which take time roughly proportional to the total test case size. We report experimental results on VoIP systems.