International Journal of Critical Computer-Based Systems (7 papers in press)
Smart Homes IoT Techniques for Dynamic Provision of Cloud Benefactors
by P. Sanjeevi, Viswanathan Perumal
Abstract: Present years have realized the expansion of computing settings for IoT (Internet of Things) amenities, which switch huge amounts of data using several devices that are continuously associated to networks. Since the information communication and amenities arise on an assortment of devices, such as household appliances, embedded devices, and sensor nodes, the dynamic provision of IoT cloud benefactors necessities are progressively important at this juncture. This work is based on IoT for home automation which is a collection of sensors controlled by microcontroller. Through microcontroller, we direct data to the cloud server for sharing the sensor data to the cloud server and accessed through mobile app. We used cloud server as Ubidots for monitoring the sensors like Gas, Flame, Sound, and Temperature. The main inspiration of this work is to alert communication through smartphone and email on any abnormal constraint. This work is intended to decrease data transmit, decrease time, cost operative and easy to use.
Keywords: Internet of Things; Cloud server; Home Automation; RFID.
Performance evaluation of a novel redundancy method for videoconferencing traffic in MPLS networks
by Mohamad Chaitou
Abstract: Performance evaluation of computer networks using mathematical modeling is widely used in assessing the advantages and drawbacks of any new mechanism before its deployment. In this contribution, we introduce a new mechanism that aims at rerouting multi-point to multi-point (MP2MP) traffic such as videoconferencing in Multi Protocol Label Switching- Traffic Engineering (MPLS-TE) networks. Then we develop a stochastic model in order to evaluate the amelioration incurred by our proposal compared to the existing approaches. In particular, we assess two criterions: the scalability and bandwidth efficiency. Our results show that our proposed method leads to better scalability while reducing the ratio of bandwidth wastage such as traffic duplication observed in the existing mechanisms. Our proposed rerouting mechanism contains two parts. First, we define the concept of MP2MP TE tunnel in MPLS as opposed to the existing MP2MP connectionless tunnel (i.e. without support of TE features such as bandwidth reservation and fast reroute in case of link and/or node failure). Second, we explain how to build a MP2MP TE bypass tunnel that is how to encapsulate a primary MP2MP TE tunnel into a backup MP2MP TE tunnel in order to provide the fast redundancy feature.
Keywords: Mathematical modeling; stochastic models; MPLS-TE; fast reroute,
Analysing Timed Compatibility of Web Service Choreography
by Maya Souilah Benabdelhafid, Béatrice Bérard, Mahmoud Boufaida
Abstract: Web Services become the most mature implementation of the Service Oriented Computing (SOC) paradigm. The verification of behavioural compatibility is then necessary to ensure correct composition of services, which depends not only on qualitative properties such as absence of deadlock but also on some quantitative properties related to performance. Most of the proposed approaches verify the composition in service orchestration modelling. However, service choreography is more collaborative in nature and describes direct interactions between services. Although many existing approaches use Petri Nets (PNs) and Colored PNs (CPNs) to analyse behavioural compatibility, few of them explore time constraints. We propose to model service interactions in a choreography with Timed CPNs and perform automatic verification and simulation using CPN Tools. We evaluate our approach with a case study from the Algerian e-Government, where we show how to verify global time constraints for the renewal of biometric passports.
Keywords: Web Service; Choreography; Compatibility; Composition; Formal Modelling; Timed CPNs; Time Constraints; Performance Analysis; Simulation; CPN Tools.
Ensuring cyber-security in smart railway surveillance with SHIELD
by Francesco Delli Priscoli, Alessandro Di Giorgio, Mariana Esposito, Andrea Fiaschetti, Francesco Flammini, Silvano Mignanti, Concetta Pragliola
Abstract: Modern railways feature increasingly complex embedded computing systems for surveillance that are moving towards fully wireless smart-sensors. Those systems are aimed at monitoring system status from a physical-security viewpoint, in order to detect intrusions and other environmental anomalies. However, the same systems used for physical-security surveillance are vulnerable to cyber-security threats, since they feature distributed hardware and software architectures often interconnected by 'open networks', like wireless channels and the internet. In this paper, we show how the integrated approach to security, privacy and dependability (SPD) in embedded systems provided by the SHIELD framework (developed within the EU funded pSHIELD and nSHIELD research projects) can be applied to railway surveillance systems in order to measure and improve their SPD level. SHIELD implements a layered architecture (node, network, middleware and overlay) and orchestrates SPD mechanisms based on ontology models, appropriate metrics and composability. The results of prototypical application to a real-world demonstrator show the effectiveness of SHIELD and justify its practical applicability in industrial settings.
Keywords: security; privacy; dependability; railway; surveillance; SHIELD.
Key management infrastructure design and novel techniques to establish secure communications in critical infrastructures
by T.C. Pramod, N.R. Sunitha
Abstract: The industrial automation and control systems (IACS) play a vital role in critical infrastructures to optimise the processes and control the activities remotely. As the proliferation of deliberate security attacks on these systems is increasing, ensuring reliable operations of these systems with safety and security is prominent. The key management infrastructure (KMI) ensures the proper management of secret keys and cryptographic keying materials which are used to secure the system. From IACS perspective, this paper addresses the security issues, challenges and parameters that need to be considered for designing an effective KMI for IACS. Also, by considering the constraints and required key management features, an efficient KMI is proposed for supervisory control and data acquisition (SCADA) systems using the polynomial key establishment scheme. The objective of the proposed KMI for SCADA systems is to support broadcasting, multicasting, join and leave, key update and pairwise communications between the SCADA devices. Comparison of the proposed scheme with existing schemes is reported.
Keywords: critical infrastructures; industrial automation and control systems; IACS; key management; key establishment; SCADA security; security; symmetric encryption.
Validation of the actual behaviour of a real-time application
by Moustapha Bikienga, Annie Choquet-Geniet, Dominique Geniet
Abstract: Classically, the temporal validation of a hard real-time application is performed using the WCET's, for instance by means of simulation. But since the actual behaviour of the application uses the ACET's which may be shorter than the WCET's, the simulated and the effective behaviours may be different. Verifying whether an application behaves in accordance to a given scheduling strategy requires to precisely specify how the application is expected to behave in the case of ACET's shorter than the WCET's. For that aim, we define two notions of compliance. The non-flexible compliance imposes the strict respect of the start times given by the simulated schedule, whereas the flexible one tolerates a higher level of conservatism. We then discuss the advantages of each, and show that using any of them preserves the validity of the behaviour of the application.
Keywords: real-time applications; scheduling; actual behaviour; validation; compliance; worst case execution time; WCET; actual execution time; ACET.
Special Issue on: ICAASE'14 Performance and Dependability Evaluation in Agent-based, Dynamic and Adaptive Systems
A layered Petri net model to formally analyse time critical web service composition
by Fateh Latreche, Faiza Belala
Abstract: Analysing flexible, open and time constrained systems like web services is of critical importance. In this work, we propose Timed Mop-ECATNets, a layered Petri net model that makes possible analysis of flexible web services while taking time and data type aspects into account. The proposed model is defined in term of the concurrent semantics of real time rewrite theories. Analysis of the model is carried out using the real time Maude TCTL model checker, instantaneous rewrite rules axiomatise instantaneous behaviour and timed rewrite rules axiomatise the timed behaviour.
Keywords: time critical web services; flexible web service composition; Petri net; real time rewrite theory.