Search

Specification languages for runtime verification are commonly rooted in formal languages, such as temporal logic, automata, or regular expressions. We argue that, for practical purposes, specification languages for monitoring should allow language features similar to those found in general purpose programming languages, in addition to providing specialized monitoring constructs. Using a realistic and large event-log, we compare two such programming-oriented monitoring language systems to a temporal logic-based monitoring system that was previously evaluated on the same log. The first programming-oriented language is a library in Scala developed for runtime verification. The other language is a scripting language, originally developed for fast static code analysis. We formulate the same reasonably complex properties as in the temporal logic case, using both methods, and compare the efficiency with which they can be checked against the large event log, and the ease with which the properties can be formulated. [ABSTRACT FROM AUTHOR]

The paper describes shortly the main principles of representative examples development, provides the essence of the methodology to develop representative examples and an example of its application. The main contribution of the paper is the methodology to develop representative examples that could be used to evaluate the sufficiency of specification language for specification of software system requirements.

Integrating simulation in the design process of production systems allows the predicted performance of design alternatives to be compared. However, many iterations of specifying the design, constructing the simulation model, performing simulation experiments, and evaluating the simulation results for each (re)design are required. The process of specifying, modelling, simulating, and evaluating a design can be automated using a framework for automated design space exploration of production systems. This paper presents a formal specification language for the design space of a production system topology. Using the specification of the design space, feasible designs can be generated. The language supports the specification of component types, component instances, and constraints such as how many instances of a type are allowed and how components are allowed to be connected. The specification language is validated through an adaptation of an industrial case study. [ABSTRACT FROM AUTHOR]

The advancement of hardware, software, and Internet infrastructure leads to the increasing quantities of smart Internet of Things (IoT) devices. Meanwhile, security issues have increasingly brought to us the concerns due to the evolving IoT scope and mass communications. Trusting service vendors depends on their devices that generate information and provide executions. Blockchain becomes an attractive choice, as evidenced by its wide adoptions. However, trusting IoT-based services becomes an important issue since the implementation of Blockchain-based IoT (BIoT) services is proprietary and independent. This paper introduces a generic architecture design that incorporates Public Key Infrastructure (PKI) to establish trust of BIoT services. This can potentially solve the trust problem and based on our experiment it can be scaled well. We also demonstrate how specification languages can be useful to express requirements. It decouples users from Blockchain and thus they can specify qualities of BIoT services without deep knowledge to work with Blockchain. [ABSTRACT FROM AUTHOR]

This article is devoted to verification of the bully election algorithm for distributed systems with TLA+ and PlusCal. In this work, we show an overview of the basic information about distributed systems, then we show definition of election algorithms for distributed systems, after that we provide a full description of the bully election algorithm for distributed systems. Later in this article, we show the model of the distributed algorithm created with TLA+ and PlusCal. Then we describe the main parts of this model. Next, we illustrate results of verification of this model. The verification was done using TLC ‒ a model checker and simulator for executable TLA+ specifications. As a result of the verification, it was possible to establish that the declared properties of safety and liveness are fully satisfied for all possible states of the system.

Due to energy efficiency and near real-time finality settlement, permissioned blockchain is mainly used in blockchain-based Internet of Things (BIoT) services. This blockchain requires validators to reach the consensuses. Currently, the validators are chosen based on generic attributes of trusted nodes capriciously. However, service users have no mechanism to provide their requirements in assessing validators. Existing works are biased from users’ perspectives, which risks collusion attacks due to improperly selected validators. This article aims to solve this by considering users’ expectations on services. A user-oriented framework is proposed to evaluate the trust of BIoT services with the consideration of validator attributes. It provides an effective mechanism to express requirements. Specification language is adopted in our algorithm to perform compliance checking. The feasibility has been verified in a simulation. We found that the permissioned blockchain has also benefited from the proposed user-oriented selection of validators in terms of computing efficiency due to additional constraints. [ABSTRACT FROM AUTHOR]

We introduce Spectra, a new specification language for reactive systems, specifically tailored for the context of reactive synthesis. The meaning of Spectra is defined by a translation to a kernel language. Spectra comes with the Spectra Tools, a set of analyses, including a synthesizer to obtain a correct-by-construction implementation, several means for executing the resulting controller, and additional analyses aimed at helping engineers write higher-quality specifications. We present the language in detail and give an overview of its tool set. Together with the language and its tool set, we present four collections of many, non-trivial, large specifications, written by undergraduate computer science students for the development of autonomous Lego robots and additional example reactive systems. The collected specifications can serve as benchmarks for future studies on reactive synthesis. We present the specifications, with observations and lessons learned about the potential use of reactive synthesis by software engineers. [ABSTRACT FROM AUTHOR]

This paper proposes a new method of combining SAT with discrete event simulation. This new integration proved useful for designing a solver for capacity analysis in early phase railway construction design. Railway capacity is complex to define and analyze, and existing tools and methods used in practice require comprehensive models of the railway network and its timetables. Design engineers working within the limited scope of construction projects report that only ad-hoc, experience-based methods of capacity analysis are available to them. Designs often have subtle capacity pitfalls which are discovered too late, only when network-wide timetables are made—there is a mismatch between the scope of construction projects and the scope of capacity analysis, as currently practiced. We suggest a language for capacity specifications suited for construction projects, expressing properties such as running time, train frequency, overtaking and crossing. Such specifications can be used as contracts in the interface between construction projects and network-wide capacity analysis. We show how these properties can be verified fully automatically by building a special-purpose solver which splits the problem into two: an abstracted SAT-based dispatch planning, and a continuous-domain dynamics with timing constraints evaluated using discrete event simulation. The two components communicate in a CEGAR loop (counterexample-guided abstraction refinement). This architecture is beneficial because it clearly distinguishes the combinatorial choices on the one hand from continuous calculations on the other, so that the simulation can be extended by relevant details as needed. We describe how loops in the infrastructure can be handled to eliminate repeating dispatch plans, and use case studies based on data from existing infrastructure and ongoing construction projects to show that our method is fast enough at relevant scales to provide agile verification in a design setting. Similar SAT modulo discrete event simulation combinations could also be useful elsewhere where one or both of these methods are already applicable such as in bioinformatics or hardware/software verification. [ABSTRACT FROM AUTHOR]

The object of research is the information and telecommunication system (ITS) and ensuring the protection of information stored, processed and circulating in it. One of the most problematic areas in the creation of secure ITS is the logical inconsistency and incompleteness of the information security policy. That is, a set of laws, rules, restrictions, recommendations, etc., which regulate the procedure for processing information and are aimed at protecting information from a certain set of threats. The reason for such problems is usually the absence of predesign modeling of the information security system as a component of the information and telecommunications system, which in the end causes the latter to be vulnerable. An important prerequisite for the creation of a secure ITS is the construction of a subject-object model of the system, which makes it possible to determine the connections between objects, their features, to model information flows and types of access to information and infrastructure resources. According to the existing clear, complete and consistent subject-object model of the ITS, it becomes possible to apply mathematical methods to modeling the processes of its functioning, including for solving the problem of formal proof of security. The paper considers the main idea of the method of formal proof of security, which can be used when building information security systems or assessing the security of the created information and telecommunications system. It is shown that for its implementation it is possible to use the methodology of automatic theorem proving. One of the ways to solve this problem, which is proposed in the work, is the use of the PVS (Prototype Verification System) formal logic system, which is widely used for writing specifications and constructing proofs. The main components of this system are considered, as well as the possibilities of its use for automatic proof of statements about the impossibility of unauthorized access under the conditions of a certain security policy. An example of the use of the PVS system for the formal proof of the security of the system in the framework of the Bella-LaPadula security policy is given. [ABSTRACT FROM AUTHOR]

The paper is dedicated to the specification of the structure and the behaviour of soft-ware libraries. It describes the existing problems of libraries specifications. A brief overview of the research field concerned with formalizing the specification of libraries and library functions is presented. The requirements imposed on the formalism designed are established; the formalism based on these requirements allows specifying all the properties of the libraries needed for automation of several classes of problems: defects detection in the software, migration of applications into a new environment, gen-eration of software documentation. The requirements on the language tools based on the developed formalism are proposed. The conclusion defines potential directions for further research.

E-commerce based application characteristics portray elevated dynamics while incorporating decentralized nature. Extreme emphasis influencing structural design plus implementation, positions such applications highly appreciated. Significant research articles reveal that, applying formal methods addressing challenges incumbent with E-commerce based applications, contribute towards reliability and robustness obliging the system. Anticipating and designing sturdy e-process and concurrent implementation, allows application behavior extra strength against errors, frauds and hacking, minimizing program faults during application operations. Programmers find extreme difficulty guaranteeing correct processing under all circumstances, however, not impossible. Concealed flaws and errors, triggered only under unexpected and unanticipated scenarios, pilot subtle mistakes and appalling failures. Code authors utilize various formal methods for reducing these flaws. Mentioning prominent methods would include, ASM (Abstract State Machines), B-Method, z-Language, UML (Unified Modelling Language) etc. This paper primarily focuses different formal methods applied while deliberating specification and verification techniques for cost effective.

Vehicle computers, Internet of Things and cyber-physical systems are all examples of electronic devices in which embedded systems require greater flexibility to process different types of applications and communication protocols. High flexibility requires the use of general purpose processors as a solution for configuring and controlling several peripherals. However, this also increases the need for hardware-dependent software. Since this is a highly critical and error-prone component due to the nature of its coding and the surrounding environment, it is essential to support the development and runtime phases through methodologies that can detect violations and errors when accessing devices by monitoring the communication protocol. This approach proposes a technique for monitoring temporal properties in high-level communication protocols between devices and drivers using a contract-based specification mechanism for describing the interface and protocol. From this specification, a monitoring module is synthesised, which can detect violation during the simulation of virtual platforms or execution of hardware platforms. The proposed specification language is a domain-specific language that supports platform-based design and enables the iteractive refinement of communication protocol and temporal property specifications along with platform stepwise implementation. Some experiments have demonstrated the effectiveness of the proposed approach for detecting errors in device drivers and device access violation.