A Spatial-Epistemic Logic for Reasoning about Security Protocols

Reasoning about security properties involves reasoning about where the information of a system is located, and how it evolves over time. While most security analysis techniques need to cope with some notions of information locality and knowledge propagation, usually they do not provide a general language for expressing arbitrary properties involving local knowledge and knowledge transfer. Building on this observation, we introduce a framework for security protocol analysis based on dynamic spatial logic specifications. Our computational model is a variant of existing pi-calculi, while specifications are expressed in a dynamic spatial logic extended with an epistemic operator. We present the syntax and semantics of the model and logic, and discuss the expressiveness of the approach, showing it complete for passive attackers. We also prove that generic Dolev-Yao attackers may be mechanically determined for any deterministic finite protocol, and discuss how this result may be used to reason about security properties of open systems. We also present a model-checking algorithm for our logic, which has been implemented as an extension to the SLMC system.Comment: In Proceedings SecCo 2010, arXiv:1102.516

Dynamic-Epistemic reasoning on distributed systems

We propose a new logic designed for modelling and reasoning about information flow and information exchange between spatially located (but potentially mobile), interconnected agents witnessing a distributed computation. This is a major problem in the field of distributed systems, covering many different issues, with potential applications from Computer Science and Economy to Chemistry and Systems Biology. Underpinning on the dual algebraical-coalgebraical characteristics of process calculi, we design a decidable and completely axiomatizad logic that combines the processalgebraical/ equational and the modal/coequational features and is developed for process-algebraical semantics. The construction is done by mixing operators from dynamic and epistemic logics with operators from spatial logics for distributed and mobile systems. This is the preliminary version of a paper that will appear in Proceedings of the second Conference on Algebra and Coalgebra in Computer Science (CALCO2007), LNCS 4624, Springer, 2007. The original publication is available at www.springerlink.co

Reconciling operational and epistemic approaches to the formal analysis of crypto-based security protocols

We propose a unifying framework for formal specification and verification of both epistemic and behavioral aspects of security protocols. The main novelty of the proposed framework is the explicit support for cryptographic constructs, which is among the most essential ingredients of security protocols. Due to this feature, the indistinguishability relation for the epistemic constructs gets a dynamic semantics by taking the communicated keys and cryptographic terms in the operational specification into account

A Taxonomy for and Analysis of Anonymous Communications Networks

Any entity operating in cyberspace is susceptible to debilitating attacks. With cyber attacks intended to gather intelligence and disrupt communications rapidly replacing the threat of conventional and nuclear attacks, a new age of warfare is at hand. In 2003, the United States acknowledged that the speed and anonymity of cyber attacks makes distinguishing among the actions of terrorists, criminals, and nation states difficult. Even President Obama’s Cybersecurity Chief-elect recognizes the challenge of increasingly sophisticated cyber attacks. Now through April 2009, the White House is reviewing federal cyber initiatives to protect US citizen privacy rights. Indeed, the rising quantity and ubiquity of new surveillance technologies in cyberspace enables instant, undetectable, and unsolicited information collection about entities. Hence, anonymity and privacy are becoming increasingly important issues. Anonymization enables entities to protect their data and systems from a diverse set of cyber attacks and preserves privacy. This research provides a systematic analysis of anonymity degradation, preservation and elimination in cyberspace to enhance the security of information assets. This includes discovery/obfuscation of identities and actions of/from potential adversaries. First, novel taxonomies are developed for classifying and comparing well-established anonymous networking protocols. These expand the classical definition of anonymity and capture the peer-to-peer and mobile ad hoc anonymous protocol family relationships. Second, a unique synthesis of state-of-the-art anonymity metrics is provided. This significantly aids an entity’s ability to reliably measure changing anonymity levels; thereby, increasing their ability to defend against cyber attacks. Finally, a novel epistemic-based mathematical model is created to characterize how an adversary reasons with knowledge to degrade anonymity. This offers multiple anonymity property representations and well-defined logical proofs to ensure the accuracy and correctness of current and future anonymous network protocol design

Discourses on social software

Can computer scientists contribute to the solution of societal problems? Can logic help to model social interactions? Are there recipes for making groups with diverging preferences arrive at reasonable decisions? Why is common knowledge important for social interaction? Does the rational pursuit of individual interests put the public interest in danger, and if so, why? Discourses on Social Software sheds light on these and similar questions. This book offers the reader an ideal introduction to the exciting new field of social software. It shows in detail the many ways in which the seemingly abstract sciences of logic and computer science can be put to use to analyse and solve contemporary social problems. The unusual format of a series of discussions among a logician, a computer scientist, a philosopher and some researchers from other disciplines encourages the reader to develop his own point of view. The only requirements for reading this book are a nodding familiarity with logic, a curious mind, and a taste for spicy debate.Kunnen de computerwetenschappers bijdragen aan een oplossing van sociale problemen? Kan logica gebruikt worden om sociale interactie te modelleren? Zijn er regels op te stellen om groepen met afwijkende voorkeuren tot redelijke besluiten te laten komen? Discourses on Social Software biedt de lezer een ideale inleiding op (nog nieuwe) gebied van sociale software. Het toont in detail de vele manieren waarin de schijnbaar abstracte wetenschappen van logica en computerwetenschap aan het werk kunnen worden gezet om eigentijdse sociale problemen te analyseren en op te lossen. Door de ongebruikelijke aanpak in dit boek, namelijk door discussies tussen een logicus, een computerwetenschapper, een filosoof en onderzoekers uit andere disciplines, wordt de lezer aangemoedigd zijn eigen standpunt te ontwikkelen. De enige vereisten om dit boek te lezen zijn enige vertrouwdheid met de logica, een nieuwsgierige geest, en liefde voor een pittig debat

PHILOSOPHICAL APPROACHES TO EVALUATING CRITICAL THINKING AS DIMINISHED EMPATHY: A QUALITATIVE ANALYSIS OF NEWS FRAMING OF STUDENT LOAN FORGIVENESS

Critical thinking has long been recognized across disciplines as being solely rooted in problem-solving and logical argument construction. By using Miranda Fricker’s Epistemic Injustice: The Power and Ethics of Knowing as a core theoretical framework, this study aims to deconstruct the ways in how news framing has shaped critical thinking over vast periods of time through an exploration into the ways in which thinking has been socially understood in an otherwise largely technologically immersed world. Using a rhetorical criticism approach, 33 news articles and segments are analyzed from a variety of popular news sources from several platforms that are commonly used mediums for information. Findings indicate that framing bias echoes hermeneutic injustice propagandizing systematic devaluation of individuated experience through use of numeric abstraction. Future research directions include an exploration into methods of cultural shift to reconsider empathy and creativity as an integral part of critical thinking as an extension of mathematics and logic

A Substructural Epistemic Resource Logic: Theory and Modelling Applications

We present a substructural epistemic logic, based on Boolean BI, in which the epistemic modalities are parametrized on agents' local resources. The new modalities can be seen as generalizations of the usual epistemic modalities. The logic combines Boolean BI's resource semantics --- we introduce BI and its resource semantics at some length --- with epistemic agency. We illustrate the use of the logic in systems modelling by discussing some examples about access control, including semaphores, using resource tokens. We also give a labelled tableaux calculus and establish soundness and completeness with respect to the resource semantics