Razvoj i analiza formalnih modela za korišćenje i deljenje resursa u distribuiranim softverskim sistemima

This thesis investigates problems of formal, mathematically based, representation and analysis of controlled usage and sharing of resources in distributed software systems. We present a model for confidential name passing, and a model for controlled resource usage. For the second model we also introduce a type system for performing a static verification that can ensure absence of unauthorized usages of resources in the system.У тези су разматрани проблеми формалног описа и анализе дељења и коришћења ресурса у дистрибуираним софтверским системима. Уведен је један рачун који моделира поверљиво дељење имена и један који моделира контролисано коришћење ресурса. За други модел предложен је и типски систем за статичку проверу који осигурава одсуство неауторизованог коришћења ресурса у систему.U tezi su razmatrani problemi formalnog opisa i analize deljenja i korišćenja resursa u distribuiranim softverskim sistemima. Uveden je jedan račun koji modelira poverljivo deljenje imena i jedan koji modelira kontrolisano korišćenje resursa. Za drugi model predložen je i tipski sistem za statičku proveru koji osigurava odsustvo neautorizovanog korišćenja resursa u sistemu

A type language for message passing component-based systems

Component-based development is challenging in a distributed setting, for starters considering programming a task may involve the assembly of loosely-coupled remote components. In order for the task to be fulfilled, the supporting interaction among components should follow a well-defined protocol. In this paper we address a model for message passing component-based systems where components are assembled together with the protocol itself. Components can therefore be independent from the protocol, and reactive to messages in a flexible way. Our contribution is at the level of the type language that allows to capture component behaviour so as to check its compatibility with a protocol. We show the correspondence of component and type behaviours, which entails a progress property for components.Comment: In Proceedings ICE 2020, arXiv:2009.0762

Zur Komplexität der Synthese von Petri-Netzen

Petri-Netz-Synthese fragt für ein reguläres Verhalten, das als Transitionssystem A gegeben ist, ob es ein Petri-Netz (einer bestimmten Klasse) gibt, das A implementiert. Diese Arbeit untersucht Varianten dieses Entscheidungsproblems für verschiedene Implementierungen und eine Vielzahl von Petri-Netz-Klassen aus Sicht der klassischen und der parametrisierten Komplexität. Ebenso wird die Komplexität der Modifikations-Techniken Neubeschriftung sowie Kanten-, Ereignis- und Zustandslöschung untersucht, die darauf abzielen, nicht-implememtierbare Transitionssysteme implementierbar zu machen.Petri net synthesis asks, for a regular behavior given as a transition system A, whether there exists a Petri net (of a particular class) that implements A. This work investigates variants of this decision problem for different implementations and a variety of Petri net classes from the point of view of classical and parameterized complexity. Also investigated is the complexity of the modification techniques of relabeling and edge, event, and state deletion, which aim to make non-implementable transition systems implementable