Toshiyuki Tsutsumi has been working for Hitachi Software Engineering Corp. since 1991, where he has developed network management software, maintained the network environment, and researched the computer networks. He has also been a student of the Graduate School of Information Science, Nara Institute of Science and Technology, Japan since 1993. He received his B.S. from the University of Electro Communications in 1991. He has been a member of the WIDE Project since 1994.
Suguru Yamaguchi received the M.E. and D.E. degrees in computer science from Osaka University, Osaka, Japan, in 1988 and 1991, respectively. From 1990 to 1992 he was an Assistant Professor in Education Center for Information Processing, Osaka University. From 1992 to 1993, he was with the Information Technology Center, Nara Institute of Science and Technology, Nara, Japan, as an Associate Professor. Currently, he is an Associate Professor with the Graduate School of Information Science, Nara Institute of Science and Technology, Nara, Japan. He has been also a member of WIDE Project, since its creation in 1987, where he has been conducting research on network security system for wide area distributed computing environment. His research interests include technologies for information sharing, multimedia communication, network security and network management for the Internet.