Biblio

Analyzing safety and security requirements remains a difficult task in the development of real-life network protocols. Although numerous modeling and analyzing methods have been proposed in the past decades, most of them handle safety and security requirements separately without considering their interplay. In this work, we propose a collaborative modeling framework that enables co-analysis of safety and security requirements for network protocols. Our modeling framework is based on a well-defined type system and supports modeling of network topology, message flows, protocol behaviors and attacker behaviors. It also supports the specification of safety requirements as temporal logical formulae and typical security requirements as queries, and leverages on the existing verification tools for formal safety and security analysis via model transformations. We have implemented this framework in a prototype tool CMSS, and illustrated the capability of CMSS by using the 5G AKA initialization protocol as a case study.

IoT networks today face a myriad of security vulnerabilities in their infrastructure due to its wide attack surface. Large-scale networks are increasingly adopting a Software-Defined Networking approach, it allows for simplified network control and management through network virtualization. Since traditional security mechanisms are incapable of handling virtualized environments, SDSec or Software-Defined Security is introduced as a solution to support virtualized infrastructure, specifically aimed at providing security solutions to SDN frameworks. To further aid large scale design and development of SDN frameworks, Model-Driven Engineering (MDE) has been proposed to be used at the design phase, since abstraction, automation and analysis are inherently key aspects of MDE. This provides an efficient approach to reducing large problems through models that abstract away the complex technicality of the total system. Making adaptations to these models to address security issues faced in IoT networks, largely reduces cost and improves efficiency. These models can be simulated, analysed and supports architecture model adaptation; model changes are then reflected back to the real system. We propose a model-driven security approach for SDSec networks that can self-adapt using machine learning to mitigate security threats. The overall design time changes can be monitored at run time through machine learning techniques (e.g. deep, reinforcement learning) for real time analysis. This approach can be tested in IoT simulation environments, for instance using the CAPS IoT modeling and simulation framework. Using self-adaptation of models and advanced machine learning for data analysis would ensure that the SDSec architecture adapts and improves over time. This largely reduces the overall attack surface to achieve improved end-to-end security in IoT environments.

The Smart Grid is the leading example when talking about complex and critical System-of-Systems (SoS). Specifically regarding the Smart Grids criticality, dependability is a central quality attribute to strive for. Combined with the desire of agility in modern development, conventional systems engineering methods reach their limits in coping with these requirements. However, approaches from model-based or model-driven engineering can reduce complexity and encourage development with rapidly changing requirements. Model-Driven Engineering (MDE) is known to be more successful in a domain specific manner. For that reason, an approach for Domain Specific Systems Engineering (DSSE) in the Smart Grid has already been specially investigated. This Model-Driven Architecture (MDA) approach especially aims the comprehensibility of complex systems. In this context, the traceability of requirements is a centrally pursued attribute. However, achieving continuing traceability between the model of a system and the concrete implementation is still an open issue. To close this gap, the present research paper introduces a Model-Centric Software Development (MCSD) solution for Smart Grid applications. Based on two exploratory case studies, the focus finally lies on the automated generation of partial implementation artifacts and the evaluation of traceability, based on dedicated functional aspects.

New generations of industrial control systems offer higher performance, they are distributed, and it is very likely that they are internet connected in one way or another. These trends raise new challenges in the contexts of reliability and security. We propose a novel approach that tackles the complexity of industrial control systems at design time and run time. At design time our target is to ease the configuration and verification of controller configurations through model-driven engineering techniques together with the contract-based design paradigm. At run time the information from design time is reused in order to support a modular and distributed self-adaptive software system that aims to increase reliability and security. The industrial setting of the presented approach are control devices for hydropower plant units.

Among the various types of Role-based access control (RBAC) policies proposed in the literature, contextual policies take into account the user's location and the time at which she requests an access. The precise characterization of the context in such policies and the definition of an access decision procedure for them are non-trivial ntasks, since they have to take into account the various facets of the temporal and spatial expressions occurring in these policies. Existing approaches for modeling contextual policies do not support all the various spatio-temporal concepts and often do not provide an access decision procedure. In this paper, we propose a model-driven approach to representing and checking RBAC contextual policies. We introduce GemRBAC+CTX, an extension of a generalized conceptual model for RBAC, which contains all the concepts required to model contextual policies. We formalize these policies as constraints, using the Object Constraint Language (OCL), on the GemRBAC+CTX model, as a way to operationalize the access decision for user's requests using model-driven technologies. We show the application of GemRBAC+CTX to model the RBAC contextual policies of an application developed by HITEC Luxembourg, a provider of situational-aware information management systems for emergency scenarios. The use of GemRBAC+CTX has allowed the engineers of HITEC to define several new types of contextual policies, with a fine-grained, precise description of contexts. The preliminary experimental results show the feasibility of applying our model-driven approach for making access decisions in real systems.