Battery lifetime remains a central constraint in scaling LoRaWAN deployments across diverse IoT applications. We propose a lightweight dilated causal Convolutional Neural Network (CNN) designed to forecast per-node energy consumption with high temporal fidelity. Unlike recurrent models, our approach captures both transient spikes and long-range patterns without sequential overhead, enabling efficient edge deployment. Trained on a 12-month NS-3 simulation dataset encompassing smart lighting, environmental monitoring, waste management, and agriculture, the model achieves 96.5% forecasting accuracy with mean absolute error below 0.3, improving over SARIMA and LSTM baselines by 55% and 32% respectively. We integrate this predictor into an end-to-end energy optimization pipeline where on-device inference executes every 15 minutes with under 5 ms overhead. Forecasts drive adaptive duty-cycling, transmission slotting, and data rate control, extending device lifetime by 20%, halving collision rates, and improving fairness by 15%. Real-world validation on ten STM32F407VG microcontrollers and a commercial RAK7258 gateway confirms practical feasibility: inference completes within 0.8 ms with 4.4 mW peak power draw and 95.6% packet delivery ratio. These results demonstrate the CNN's suitability for real-time, edge-centric forecasting and its potential for enabling sustainable, intelligent LoRaWAN networks.

ABSTRACT Industrial automation and smart ecological monitoring are key fields of Internet of Things environments, where devices function under complex practical conditions and with restricted infrastructure. In such conditions, devices often face critical concerns in guaranteeing trustworthiness and better outcomes. In this article, we preliminarily suggest a thoughtful design that anticipates the programming complexities of Internet of Things (IoT) environments and accounts for their unpredictable conduct under practical conditions. Central to our strategy is the use of a method grounded in mathematical logic to allow their core properties to be rigorously checked through mathematical proofs. This process builds trustworthy IoT infrastructures and ensures dependability of their conduct before practical programming. Beyond theoretical design, we perform programming and field experiments, demonstrating that mathematically grounded designs lead directly to more productive environment outcomes, particularly in restricted conditions where infrastructure must be exploited judiciously. The results underscore the value of integrating our mathematically checked design not only at the design level but also in shaping concrete solutions for critical blockchain‐enabled IoT environments. Finally, the results show that applying our design translates into demonstrable outcomes and easier environment adaptation during practical programming.

ABSTRACT During the early phases of software system development, error detection can be challenging due to the complexity of both the requirements and the operating environments. This paper advocates for the utilization of formal modelling and verification throughout the first phases of systems development to promptly detect and correct errors. The formalism employed throughout is Event‐B, which is backed by the Rodin toolset. To conquer requirements complexity, the frameworks of set theory and first‐order logic are employed, which provide the necessary tools for formalizing and analysing the properties and behaviours associated with Event‐B. Also, we detail the way in which modelling may be used to achieve abstraction, as well as the way in which refinement can be used to manage complexity through layering. Furthermore, we emphasize the significance of model validation and verification in improving the precision of formal models and requirements in IoT communication systems. The model is exemplified using a Content‐Based Publish Subscribe System (CBPS), with a special emphasis on a fire alarm system as a motivating example.

IoT-Cloud environments are being increasingly adopted for the deployment of applications and particularly resource-oriented ones. However, ensuring correct communications during the execution of IoT applications is not guaranteed. In fact, a substantial class of applications is intended to run on constrained IoT networks. Moreover, IoT devices exchange the data derived from various Cloud providers and in accordance with different protocols. In this paper, we propose a formal approach to model and verify the applications deployed over IoT-Cloud environments. The proposed model encompasses four verification levels: the Structural, Functional, Operational and Behavioral levels. Therefore, we opted for the Event-B formal method that allows gradual problems decomposition by relying on its refinement capabilities. The proposed approach has proven its efficiency for the modeling and the verification of IoT applications. We applied mathematical proof-based method to verify the model since it provides rigorous reasoning. We also employed the ProB animator to proceed in the validation of the model.

Conceptual clustering is a well-studied research area in the field of unsupervised machine learning. It aims to identify disjoint clusters, where each cluster represents a collection of similar transactions described by a common pattern. The first phase of earlier conceptual clustering methods relies on the enumeration of closed patterns. Nevertheless, the extraction of such patterns can be challenging, primarily due to their rigorous nature. Indeed, closed patterns can be not frequent or fail to cover all the transactions within a cluster. To overcome this issue, this paper presents a novel approach based on the relaxation of frequent patterns called k-relaxed frequent patterns. Then, we introduce a propositional satisfiability method for enumerating such patterns. Afterwards, we employ an integer linear programming approach to compute the set of disjoint clusters. Finally, we demonstrate the efficiency of our approach through an extensive experiments conducted on several popular real-life datasets.

Community detection in social networks is a significant area of research within Artificial Intelligence and social network analysis. The agglomerative method is a well-known approach used for detecting communities. This technique relies on local similarities, to form clusters between pairs of nodes in the graph. The process involves merging each pair of nodes that exhibits the highest similarity and then computing a quality function for the current clustering results; each such merge, along with the computation of the quality of results, constitutes a step or called iteration. The choice of a similarity function can play a crucial role in determining the number of iterations, which in turn affects the running time of an agglomerative method. This raises a fundamental question when employing an agglomerative approach: a worth-asking question is how to determine which similarity function to choose and why. To address this question, our paper delves into the comparison of two well-known similarity functions: structural similarity and hub-promoted similarity. We conducted a deep comprehensive theoretical analysis followed by an extensive experimentation on several datasets, focusing on the computational aspects of these functions. Notably, our findings highlight that in specific cases within the graph, the hub-promoted similarity function is faster compared to structural similarity.

Internet of Things (IoT) is a finite set of interconnected devices that can cooperate and interact with each other through the Internet. As the number of IoT devices have increased, the number of services increased as well, further complicating the process of service composition. In this paper, an Event-B formal model is presented to verify the correctness of the IoT service composition (IoTSC) system. In addition, the proposed model satisfies some functional and non-functional properties such as compatibility and availability to fulfil the requirements of the IoTSC. Our model is developed incrementally from abstract level to target level by using the refinement mechanism. A Fire Alarm Detection System is used as a case study for our model. Finally, we use proof obligations and the Rodin platform to validate and proof the correctness of the proposed formal model.

The Internet of Things (IoT) comprises a group of interconnected devices that communicate through the internet, necessitating a robust infrastructure and security protocols. Within this ecosystem, the Content-based Publish-Subscribe (CBPS) messaging paradigm enables devices to subscribe to specific data or events. However, as the number of messages transmitted increases, ensuring reliable transmission and accurate event matching becomes a challenging task. To tackle this issue, this study proposes an Event-B formal model for verifying the correctness of IoT CBPS communication. The model aims to guarantee that messages are delivered to the intended devices while ensuring the appropriate use of context information for filtering messages. Furthermore, the model's consistency has been verified using Event-B tools.

Nowadays, The Internet of Things(IoT) has shown an increased interest in the academic literature, while its implementations became involved in almost every aspect of life in modern society. IoT is the integration of virtual and physical things through distributed services to collect and share data among themselves. The number of architecture approaches designed to aid IoT has increased significantly recently. As a result of different IoT architecture approaches, in this paper, we proposed a novel correct-by-construction formal approach based on an Event-B method to describe the physical architecture of IoT layers. This formal approach inspects four layers: the physical layer, the gateway layer, the middleware layer, respectively the application layer. An Electrocardiogram (ECG) IoT system is applied in our model as a case study. Finally, we proved and validated the correctness of our formal model by using proof obligations and the model checking tool called Rodin.

Abstract Many disciplines have adopted component-based principles to avail themselves of the many advantages they bring, especially component reusability. In a short time, the component-based architecture became a renown branch in the IT world and the center of interest of many researchers. Much work has been conducted in this context for the verification of component-based applications (CBAs). However, the main focus has been on the structural aspect of such compositions, while the behavioral aspect has seldom been dealt with. In this paper, our goal is to close this gap and propose a formal approach to verify the behavioral correctness of CBAs. We first define a set of requirements to be satisfied by the structure and the behavior of a CBA, represented by a set of interactions that may occur between their components. Then, we build a formal Event-B model to represent these requirements in a rigorous and non-ambiguous way. The use of the Event-B refinement technique allows us to master the complexity of CBAs by introducing their elements in an incremental manner. The correctness of the development is ensured by establishing a set of proof obligations, under the Rodin platform, and also by animating it with the ProB animator/model checker. The approach is illustrated by a running example.

Fog computing is a new paradigm where cloud services are extended to the edge of the network. Fog nodes offer several services called fog services. These latter can accomplish Internet of Thing (IoT) applications. An IoT application is composed of a set of tasks, where each one of them can be provided by one or more fog services. In this work, we focus on the problem of assigning for each IoT task a fog service. We aim to guarantee the reliability of the assignment process. For purpose, we propose a requirements-aware fog services composition approach. Such an approach dynamically assigns tasks issued from IoT devices to a set of fog services. This assignment process is based on a set of transactions rules, which express which faults are tolerable, retriable, or recoverable. The proposed approach is based on a genetic algorithm (GA). Empirical studies are conducted to evaluate the performance of the proposed approach.

While Blockchains can open intriguing opportunities of research in many application contexts, they come with the risk of bringing new unconventional problems. In fact, because of the monetary value they hold, Blockchains have been subject to many attacks. Smart contracts, which are at the core of second-generation Blockchains, have been proven to be the origin of such attacks due to the exploitable vulnerabilities their code may hold. It is therefore an essential requirement to prove the correctness of the smart contracts to be deployed on a Blockchain to ensure its protection. The existing approaches have been focusing on targeting generic vulnerabilities like reentrancy, without offering the possibility to check temporal-based contract-specific properties. In this paper, we aim to address smart contracts verification while supporting such properties. We propose and implement a transformation of Solidity smart contracts into Coloured Petri nets and investigate the capability of existing model checking tools to check specific temporal properties of the formally modeled contract.

Abstract The verification of the Cloud composite services’ correctness is challenging. In fact, multiple component services, derived from different Cloud providers with different service description languages and communication protocols, are involved in the composition which may raise incompatibility issues that in turn lead to a non-consistent composition. In this work, we propose a formal approach to model and verify Cloud composite services. Four verification levels are considered in this article; the structural, semantic, behavioral, and resource allocation levels. Therefore, we opted for the Event-B formal method that enables complex problems decomposition thanks to its refinement capabilities. The proposed approach has proven its efficiency for the modelling and verification of Cloud composite services. The proposed model comprises four abstract levels with respect to the four verification axes. A proof-based approach is applied to the model’s verification. We also succeeded in the validation of the model thanks to the model animation provided by the PROB tool. The use of formal methods provides a rigorous reasoning and mathematical proofs on the correction of the model which ensures the elaboration of correct-by-construction composite services.

Reusability is a central concept of Web services as it allows for the construction of composite services. Thus, an existing composite service can be combined with other composite services to form more complex nested or hierarchical services. Reliability and efficiency are the main requirements of composite services construction. The reliability requirements are rigorously defined by designers using the accepted termination states concept. The efficiency requirements are tightly related to a set of quality-of-service (QoS) constraints that are required by customers. In this paper, we first developed a hierarchical model for composite services. Based on this model, we developed a recursive procedure for the automatic computation of the transactional reliability and QoS of composite services. Second, we proposed a new concept, called required efficiency level, to offer more flexibility to the customers to specify their needs in terms of QoS. Third, we developed a new composite service configuration (CSC) algorithm for the construction and adaptation of composite services while considering the reliability and efficiency requirements. The originality of the CSC algorithm consists in a new recursive global QoS constraint decomposition procedure. Finally, we conducted a set of experiments to evaluate the benefits of the proposed CSC algorithm in comparison with the related work. These experiments confirm that our CSC algorithm is able to generate, in a timely fashion, reliable, and efficient composite services.

This report gives a brief overview of the main concerns addressed by the authors at the fifth international track on Formal Verification of Service Based Systems, held at WETICE 2017 conference. A presentation of the main topics is given and then a summary of the paper accepted by this conference track is reported.

Abstract Cloud environments are being increasingly used for the deployment and execution of complex applications and particularly component-based ones. They are expected to provide elasticity, among other characteristics, in order to allow a deployed application to rapidly change the amount of its allocated resources in order to meet the variation in demand while ensuring a given Quality of Service (QoS). However, establishing a correct elastic component-based application is not guaranteed in Cloud. Indeed, applying elasticity mechanisms should preserve functional properties and improve non-functional properties related to QoS, performance and resource consumption. In this paper, we propose an approach for the verification and deployment of elastic component-based applications. Our approach is based on the Event-B formal method. In fact, we formally model the component artifacts using Event-B and we define the Event-B events that model the elasticity mechanisms (scaling up and down) for component-based applications. Furthermore, we formally verify that our approach preserves the semantics of the component-based applications by using the proof obligations and the ProB animator. Once the elastic component-based applications are validated, they can be deployed in a Cloud environment using an elastic deployment framework which we have developed.

Cloud environments are being increasingly used for deploying and executing business processes to provide a high level of performance with low operating cost. Nevertheless, due to the lack of an explicit and formal description of the resource perspective in the existing business processes, the correctness of Cloud resources management can not be verified. The aim of the present work is to offer a formal definition of the resource perspective in business processes as a step towards ensuring a correct and consistent Cloud resource allocation in business process modeling. Concretely, we propose a formalism based on the Event-B language for specifying Cloud resource allocation policies in business process models. This formal specification is used to formally validate the consistency of Cloud resource allocation for process modeling at design time, and to analyze and check its correctness according to user requirements and resource capabilities. In order to show its feasibility, our approach has been tested using a real use case study from an industrial partner.

Nowadays, a growing number of companies are using Cloud Computing to optimize their business processes by using dynamically scalable and often virtualized resources on demand. Nevertheless, due to the lack of explicit and formal description of the resource perspective in existing business processes, Cloud resource allocation behavior cannot be efficiently and correctly managed. In this paper, we aim at formally verifying resource allocation in business processes using Event-B. More precisely, our aim is to specify the resource allocation behavior both at design time and at runtime, and to check its correctness according to users' needs. Our model also takes into account different cloud properties such as elasticity and shareability. In order to show its feasibility, our approach has been tested using a use case study from an industrial partner.

A configurable process model captures a family of similar processes. Such models can be configured to obtain a process variant according to specific requirements. With this aim, several approaches have been proposed for the configuration of process models. Nevertheless, an increasing attention is being paid to achieve this in a sound manner due to the complex inter-dependencies between the configuration decisions. In this work, we aim to guide the process analyst to easily configure process models while preserving soundness. To do so, we propose a formal approach for ensuring correctness of business process configurations while considering structural constraints they have to obey. Specifically, using the Event-B language, we formally define a configurable process model, its correctness-preserving conditions and its configuration constraints.

This report gives a brief overview of the main concerns addressed by the authors at the fourth international track on Formal Verification of Service Based Systems, held at WETICE 2016 conference. A presentation of the main topics is given and then a summary of the paper accepted by this conference track is reported.

The main issues for the fulfillment service level agreements (SLA) are concerned with problem of variability of QoS properties (vQoS). Indeed, the QoS properties may evolve frequently either because of internal changes or because of workload fluctuations. To solve the vQoS problem, we first introduced three variability operators: replicate, delete and replace. These operators will be used to reconfigure CWS when the SLA contract is violated. The first two operators are used to add and remove Web service instances, while the last one is used to substitute some faulty Web services. Then, we proposed an incremental approach for modeling and verifying the composites services (CWSs) reconfiguration using Event-B. We start by abstractly specifying the main requirements and then we refine them through several steps to model CWSs. The consistency of each model and the relationship between an abstract model and its refinements are obtained by formal proofs. Finally, we used ProB model-checker to trace possible design errors. We have exploited the LTL for dynamic reconfigurations to characterize the correct behavior of CWSs reconfiguration.

With the emergence of Service Component Architecture (SCA), all interests were focused on representing this architecture in a formal way in order to be able to prevent the specifications failures. In this context, our recent works were interested in formalizing structural properties of the SCA specifications, particularly in defining structural compatibility between connected services. In fact, verifying structural compatibility is necessary but not sufficient. In this paper we intend to represent, in a first step, the SCA behavioral properties by means of Event-B invariants and events. In a second step, we established behavioral compatibility between services interacting together which is considered as a delicate task and has a great importance in guaranteeing reliable communication between services. The consistency and the validity of the obtained model have been proved by the Event-B dedicated tools.

With the emergence of Service Component Architecture (SCA), all interests were focused on representing this architecture in a formal way in order to be able to prevent the specifications failures. In this context, our recent works were interested in formalising structural properties of the SCA specifications, particularly to defining structural compatibility between connected services. In fact, verifying structural compatibility is necessary but not sufficient. In this paper we intend to represent, in a first step, the SCA behavioral properties by means of Event-B invariants and events. In a second step, we established behavioral compatibility between services interacting together which is considered as a delicate task and has a great importance in guaranteeing reliable communication between services. At last, we propose an Event-B based approach so as to configure the SCA composition dynamically. We focus, particularly, on the correctional dynamic such as substituting faulty services and components. The consistency and the validity of the obtained model have been proved by the Event-B dedicated tools.

This report gives a brief overview of the main concerns addressed by the authors at the third international track on Formal Verification of Service Based Systems, held at WETICE 2015 conference. A presentation of the main topics is given and then a summary of the paper accepted by this conference track is reported.

Service Component Architecture (SCA) is a set of specifications which describe a model for building applications and systems using a Service-Oriented Architecture (SOA). However, SCA in its current form does not represent any formal definition. In addition, there is a growing interest for verification techniques which help to prevent SCA composition specification failure. In this context, we intend to propose an Event-B based approach so as to configure the SCA composition dynamically. We focus, particularly, on the correctional dynamic such as substituting faulty services and components. The consistency and the validity of the obtained model have been proved by the Event-B dedicated tools.

In this paper, we propose a new paradigm, called dynamic transactional pattern, for specifying flexible and reliable composite Web services in a pervasive environment. This new paradigm is a convergence concept of dynamic Workflow patterns and advanced transactional model. It can be seen both as a dynamic coordination and a structural transaction. Indeed, it combines dynamic Control-Flow flexibility and transactional processing reliability.

This report gives a brief overview of the main concerns addressed by the authors at the second international track on Formal Verification of Service Based Systems, held at WETICE 2014 conference. A presentation of the main topics is given and then a summary of the paper accepted by this conference track is reported.

Verifying Web service composition in a dynamic environment remains one of the most difficult tasks despite the efforts and the previous proposed research works because new services can be composed during the execution step and others can automatically appear, disappear, or be updated. To achieve the Web service composition specification and verification, we introduce a new concept, called dynamic pattern. A dynamic pattern is an extension of a static one. Then, we propose to formalize dynamic Web Service composition in Event-B using dynamic patterns. The resulting model is progressively verified using proofs. We use animator of model (ProB) to detect a variety of problems, such as deadlocks or other unexpected behavior of a model.

Service Component Architecture specification (SCA) is an emerging and promising technology for the development, deployment and integration of Internet applications. This technology supports the management of dynamic availability and treats the heterogeneity between the components of distributed applications. However, this technology is not able to solve all problems. Currently, software systems are evolving. This factor makes development, verification and maintenance of systems more complex than before. One solution to remedy this was the use of the Model Driven Engineering (MDE) approach in the development and verification process. The purpose of this paper is to apply an approach MDE to obtain SCA models and to verify the properties of these models. To reach our purpose, we applied two transformations: The first one to obtain SCA models using UML 2.0 metamodel and the second transformation to ensure the verification of the properties of these models using event-B metamodel. To achieve this, we study the UML 2.0 component metamodel, the SCA metamodel and the event-B metamodel. We have defined transformation rules in ATL language.

In this paper, the work developed aims at contributing to the research related to the Quality of Service (QoS) for Web services. The aim of this research is twofold, first, it helps the designers and developers to provide better web services and second, and it helps ensure consistent software architecture as a reference model for many applications. To achieve this, we model, first, the meta-QoS model of the Web services. Then, we formalize the QoS of the Web services by referring to ARMANI. We also, handle the mediation of the composite Web services with the ACME using an automatic MDE approach and implementing a tool for this aim: Web services compositions are transformed onto ACME specifications.

SOA (Service Oriented Architecture) defines a new Web services cooperation paradigm in order to develop distributed applications using reusable services. The handling of such collaboration has different problems that lead to many research efforts. In this paper, we address the problem of Web service composition. Indeed, various heterogeneities can arise during the composition. The resolution of these heterogeneities, called mediation, is needed to achieve a service composition. In this paper, we propose a sound approach to formalize Web services composition mediation with the ADL (Architecture Description Language) ACME. To do so, we first model the meta model of composite service manager and mediation. Then we specify semi formal properties associated with this meta model using OCL (Object Constraint Language). Afterwards, we formalize the mediation protocol using Armani, which provides a powerful predicate language in order to ensure service execution reliability.