With the years, program complexity has increased dramatically: ensuring program correctness has become considerably more difficult with the advent of multithreading, security has grown more prominent during the last decade, etc. As a result, static verification has become more important than ever. Automated verification tools exist, but they are only able to prove a limited set of properties, s...

Modern networked enterprises can preserve their competitive edge only by adopting a modern architecture for their computing systems, and thus, become agile with respect to changes in computing technologies, for pressures for modifications in external business processes, and for management of simultaneous and changing memberships in various business networks. Establishment of virtual enterprises...

— The electric power transmission systems of tomorrow must incorporate advanced hardware and software technologies to increase reliable long-distance power transfer. While new hardware technologies can improve transmission system capabilities, software technologies are also needed to coordinate these hardware technologies safely, securely, and effectively. To prevent system failures, future tra...

The primary focus of my research is the computer-aided verification and validation of computer systems, including concurrent and distributed systems; security, network and wireless protocols; software systems; biological systems; and safety-critical and embedded systems. Throughout my career I have been interested in both the computational complexity and algorithmica of verification, striving t...

Reachability analysis of infinite-state systems plays a central role in many verification tasks. In the last decade, SMT-Solvers have been exploited within many verification tools to discharge proof obligations arising from reachability analysis. Despite this, as of today there is no standard language to deal with transition systems specified in the SMT-LIB format. This paper is a first proposa...

Hybrid systems exhibit both discrete and continuous dynamics. The system state can flow continuously, and can also jump by triggering an event (transition). As an important application in the research of hybrid systems, safety verification is concerned with whether a specified set of unsafe states can be reached by the system from the initial set. One direct approach is to compute or over-appro...

Software Verification with Program-Graph Interpolation and Abstraction Aws Albarghouthi Doctor of Philosophy Graduate Department of Computer Science University of Toronto 2015 Picture a world where you can ask questions about a piece of code and have tools that automatically and efficiently answer them for you. Can a division by zero ever occur? Are all elements in this list always greater than...

In this paper, aimed at dependently typed programmers, we present a novel connection between automated and interactive theorem proving paradigms. The novelty is that the connection offers a better trade-off between usability, efficiency and soundness when compared to existing techniques. This technique allows for a powerful interactive proof framework that facilitates efficient verification of ...

The current practice of finding programming errors in operating system development is by testing and debugging. However, testing techniques are expensive because of their requirement of manual labour. Furthermore, they are susceptible to missing severe errors. This problem can be solved by applying automated verification techniques such as software model checking. Most of these techniques suffe...

Safety-critical software-dependent systems such as those found in the avionics, automotive, maritime, and energy domains often need to be certified based on one or more safety standards. An important prerequisite for demonstrating compliance to software safety standards such as IEC 61508 is the collection of safety evidence. Without an upfront agreement between the system supplier and the certi...