Automated incremental software verification

Software continuously evolves to meet rapidly changing human needs. Each evolved transformation of a program is expected to preserve important correctness and security properties. Aiming to assure program correctness after a change, formal verification techniques, such as Software Model Checking, have recently benefited from fully automated solutions based on symbolic reasoning and abstraction. However, the majority of the state-of-the-art model checkers are designed that each new software version has to be verified from scratch. In this dissertation, we investigate the new Formal Incremental Verification (FIV) techniques that aim at making software analysis more efficient by reusing invested efforts between verification runs. In order to show that FIV can be built on the top of different verification techniques, we focus on three complementary approaches to automated formal verification. First, we contribute the FIV technique for SAT-based Bounded Model Checking developed to verify programs with (possibly recursive) functions with respect to the set of pre-defined assertions. We present the function-summarization framework based on Craig interpolation that allows extracting and reusing over- approximations of the function behaviors. We introduce the algorithm to revalidate the summaries of one program locally in order to prevent re-verification of another program from scratch. Second, we contribute the technique for simulation relation synthesis for loop-free programs that do not necessarily contain assertions. We introduce an SMT-based abstraction- refinement algorithm that proceeds by guessing a relation and checking whether it is a simulation relation. We present a novel algorithm for discovering simulations symbolically, by means of solving ∀∃-formulas and extracting witnessing Skolem relations. Third, we contribute the FIV technique for SMT-based Unbounded Model Checking developed to verify programs with (possibly nested) loops. We present an algorithm that automatically derives simulations between programs with different loop structures. The automatically synthesized simulation relation is then used to migrate the safe inductive invariants across the evolution boundaries. Finally, we contribute the implementation and evaluation of all our algorithmic contributions, and confirm that the state-of-the-art model checking tools can successfully be extended by the FIV capabilities

Optimization of BGP Convergence and Prefix Security in IP/MPLS Networks

Multi-Protocol Label Switching-based networks are the backbone of the operation of the Internet, that communicates through the use of the Border Gateway Protocol which connects distinct networks, referred to as Autonomous Systems, together. As the technology matures, so does the challenges caused by the extreme growth rate of the Internet. The amount of BGP prefixes required to facilitate such an increase in connectivity introduces multiple new critical issues, such as with the scalability and the security of the aforementioned Border Gateway Protocol. Illustration of an implementation of an IP/MPLS core transmission network is formed through the introduction of the four main pillars of an Autonomous System: Multi-Protocol Label Switching, Border Gateway Protocol, Open Shortest Path First and the Resource Reservation Protocol. The symbiosis of these technologies is used to introduce the practicalities of operating an IP/MPLS-based ISP network with traffic engineering and fault-resilience at heart. The first research objective of this thesis is to determine whether the deployment of a new BGP feature, which is referred to as BGP Prefix Independent Convergence (PIC), within AS16086 would be a worthwhile endeavour. This BGP extension aims to reduce the convergence delay of BGP Prefixes inside of an IP/MPLS Core Transmission Network, thus improving the networks resilience against faults. Simultaneously, the second research objective was to research the available mechanisms considering the protection of BGP Prefixes, such as with the implementation of the Resource Public Key Infrastructure and the Artemis BGP Monitor for proactive and reactive security of BGP prefixes within AS16086. The future prospective deployment of BGPsec is discussed to form an outlook to the future of IP/MPLS network design. As the trust-based nature of BGP as a protocol has become a distinct vulnerability, thus necessitating the use of various technologies to secure the communications between the Autonomous Systems that form the network to end all networks, the Internet

Fourth Conference on Artificial Intelligence for Space Applications

Proceedings of a conference held in Huntsville, Alabama, on November 15-16, 1988. The Fourth Conference on Artificial Intelligence for Space Applications brings together diverse technical and scientific work in order to help those who employ AI methods in space applications to identify common goals and to address issues of general interest in the AI community. Topics include the following: space applications of expert systems in fault diagnostics, in telemetry monitoring and data collection, in design and systems integration; and in planning and scheduling; knowledge representation, capture, verification, and management; robotics and vision; adaptive learning; and automatic programming

Proceedings of the 21st Conference on Formal Methods in Computer-Aided Design – FMCAD 2021

The Conference on Formal Methods in Computer-Aided Design (FMCAD) is an annual conference on the theory and applications of formal methods in hardware and system verification. FMCAD provides a leading forum to researchers in academia and industry for presenting and discussing groundbreaking methods, technologies, theoretical results, and tools for reasoning formally about computing systems. FMCAD covers formal aspects of computer-aided system design including verification, specification, synthesis, and testing

Computer Aided Verification

The open access two-volume set LNCS 11561 and 11562 constitutes the refereed proceedings of the 31st International Conference on Computer Aided Verification, CAV 2019, held in New York City, USA, in July 2019. The 52 full papers presented together with 13 tool papers and 2 case studies, were carefully reviewed and selected from 258 submissions. The papers were organized in the following topical sections: Part I: automata and timed systems; security and hyperproperties; synthesis; model checking; cyber-physical systems and machine learning; probabilistic systems, runtime techniques; dynamical, hybrid, and reactive systems; Part II: logics, decision procedures; and solvers; numerical programs; verification; distributed systems and networks; verification and invariants; and concurrency

FORMAL ANALYSIS OF WEB SERVICE COMPOSITION

Ph.DDOCTOR OF PHILOSOPH

Computer Aided Verification

The open access two-volume set LNCS 11561 and 11562 constitutes the refereed proceedings of the 31st International Conference on Computer Aided Verification, CAV 2019, held in New York City, USA, in July 2019. The 52 full papers presented together with 13 tool papers and 2 case studies, were carefully reviewed and selected from 258 submissions. The papers were organized in the following topical sections: Part I: automata and timed systems; security and hyperproperties; synthesis; model checking; cyber-physical systems and machine learning; probabilistic systems, runtime techniques; dynamical, hybrid, and reactive systems; Part II: logics, decision procedures; and solvers; numerical programs; verification; distributed systems and networks; verification and invariants; and concurrency

Automated Verification of Complete Specification with Shape Inference

Ph.DDOCTOR OF PHILOSOPH