Dr. Adarshpal S. Sethi is a professor in the Department of Computer and Information Sciences at the University of Delaware, where he currently teaches a course on the simulation of computer networks that is based entirely on the use of OPNET for network simulation. Dr. Sethi is a member of the editorial boards of the IEEE Transactions on Network and Service Management, International Journal of Network Management, and Electronic Commerce Research Journal. His research interests include architectures and protocols for network management, fault management, management of wireless networks, and network simulation and modeling. Dr. Vasil Y. Hnatyshin is an associate professor in the Department of Computer Science at Rowan University, where he has successfully integrated OPNET software into courses such as data communications and computer networks and TCP/IP and Internet technologies. His research interests include QoS in the Internet, TCP/IP networks, location-aided routing in mobile ad hoc networks, network security, wireless communication, and network simulation and modeling.