The project will develop techniques for monitoring systems to check if their executions satisfy a property specified by an automaton or a temporal logic specification. Systems to be monitored are modeled as a stochastic system. The project proposes accuracy measures that denote how accurately the desired property is monitored. The research will implement the accuracy measures as monitors for such systems. The research will also develop active monitors that interact with the underlying system to ensure the correctness properties, as well as techniques for detection of failures from a system?s external behavior and static verification techniques based on model checking employing symmetry based reduction. The work will lead to mathematically rigorous and powerful techniques that will improve the reliability of increasingly complex systems.
Computer Systems are ubiquitous in modern society. They occur in our smartphones,home computers and in automobiles and various appliances. It is critically important to ensure correct functioning of these systems. The project developed two broad types of techniques for ensuring this objective. The first type of technique is meant for use during the operation of computer system is deployed. During this time, it continuously monitors the system to ensure that it functions correctly. Any improper behavior is detected as soon as it occurs. The developed techniques ensure that the monitors are as accurate as possible so that they detect all bad behaviors, and only the bad behaviors, in a timely manner. The second class of techniques, developed in the project, ensure the correct design and development of such systems before their deployment. The broader impacts of the project include correct design, development and deployment of safe computer systems. This will reduce the down time of computer systems leading to economic benefits and will also make it more difficult to break into systems thus making them safer. It will thus allow informationtechnology to be more widely and safely used in the society. The project also developed academic courses dealing with various topics of research and trained graduate students in the research area.