A Graph Transformation Approach to Software Architecture Reconfiguration

The ability of reconfiguring software architectures in order to adapt them to new requirements or a changing environment has been of growing interest. We propose a uniform algebraic approach that improves on previous formal work in the area due to the following characteristics. First, components are written in a high-level program design language with the usual notion of state. Second, the approach deals with typical problems such as guaranteeing that new components are introduced in the correct state (possibly transferred from the old components they replace) and that the resulting architecture conforms to certain structural constraints. Third, reconfigurations and computations are explicitly related by keeping them separate. This is because the approach provides a semantics to a given architecture through the algebraic construction of an equivalent program, whose computations can be mirrored at the architectural level

Modelling Software Evolution using Algebraic Graph Rewriting

We show how evolution requests can be formalized using algebraic graph rewriting. In particular, we present a way to convert the UML class diagrams to colored graphs. Since changes in software may effect the relation between the methods of classes, our colored graph representation also employs the relations in UML interaction diagrams. Then, we provide a set of algebraic graph rewrite rules that formalizes the changes that may be caused by an evolution request, using the pushout construction in the category of marked colored graphs

Putting Teeth into Open Architectures: Infrastructure for Reducing the Need for Retesting

Proceedings Paper (for Acquisition Research Program)The Navy is currently implementing the open-architecture framework for developing joint interoperable systems that adapt and exploit open-system design principles and architectures. This raises concerns about how to practically achieve dependability in software-intensive systems with many possible configurations when: 1) the actual configuration of the system is subject to frequent and possibly rapid change, and 2) the environment of typical reusable subsystems is variable and unpredictable. Our preliminary investigations indicate that current methods for achieving dependability in open architectures are insufficient. Conventional methods for testing are suited for stovepipe systems and depend strongly on the assumptions that the environment of a typical system is fixed and known in detail to the quality-assurance team at test and evaluation time. This paper outlines new approaches to quality assurance and testing that are better suited for providing affordable reliability in open architectures, and explains some of the additional technical features that an Open Architecture must have in order to become a Dependable Open Architecture.Naval Postgraduate School Acquisition Research ProgramApproved for public release; distribution is unlimited

Graph-based formalism for Machine-to-Machine self-managed communications

International audienceMachine-to-Machine communications comprise a large number of intelligent devices sharing information and making cooperative decisions without any human intervention. To support M2M requirements and applications which are in perpetual evolution, many standards are designed, updated and rendered obsolete. Among these, arise from The European Telecommunications Standards Institute (ETSI) a promising standard for M2M communications. The ETSI M2M provides in particular a standardized framework for interoperable M2M Services. As most of its peer, this standard does not, however, address the issue of dynamic reconfiguration or provide a suitable model for the reasoning required to build self-managed M2M architectures. In our paper, we propose a graph-based approach built on top of the ETSI standard, including rules for reconfiguration management, to enforce self-management properties of M2M communications

Engineering Delta Modeling Languages

Delta modeling is a modular, yet flexible approach to capture spatial and temporal variability by explicitly representing the differences between system variants or versions. The conceptual idea of delta modeling is language-independent. But, in order to apply delta modeling for a concrete language, so far, a delta language had to be manually developed on top of the base language leading to a large variety of heterogeneous language concepts. In this paper, we present a process that allows deriving a delta language from the grammar of a given base language. Our approach relies on an automatically generated language extension that can be manually adapted to meet domain-specific needs. We illustrate our approach using delta modeling on a textual variant of statecharts.Comment: 10 pages, 8 figures. Proceedings of the 17th International Software Product Line Conference, Tokyo, September 2013, pp.22-31, ACM, 201

Modeling the Artificial Immune System to the Human Immune System with the Use of Agents

The purpose of this study is to provide a model and a work frame to approximate the artificial immune system to the human immune system with the use of agents to counter malicious software (malware). The artificial immune system components are commercial off-the-shelf products that are managed by the agent that coordinate and synchronize their activity. The behavior of the agent is a simulation of the B-cells in the Human Immune System in the encapsulation, analysis and digestion of the antigen. The proposed architecture can be implemented in almost certainty based on the use of the commercial off-the-shelf products (COTS). The agent can be constructed to perform the required functionality with the help of the sandbox tools that provide the encapsulation. Anomaly detectors provide the knowledge of any process' action that is considered abnormal, hence, a possible malware. The Antivirus applications provide the digestion of the antigen, where known malware is handled directly, while unknown malware is analyzed by signature extraction, then handled by the antivirus. Other components such as intrusion detection (ID) applications perform the defenses at the entrances to the system (communication channels) and the firewall applications provide the prevention of the spread of the antigen and quarantining it in the infected node. The implementation of the model will provide a parallel self-healing system against antigens along side the applications and hardware self-healing systems.Computer Science Departmen

Volume I: Acquisition Research: The Foundation for Innovation

Proceedings Paper (for Acquisition Research Program)Accordingly, the year 2006 was especially significant for the NPS Acquisition Research Program in taking major strides toward expanding the program''s reach in important ways to other institutions.'' The number of research institutions participating as collaborators grew to 35 with the formation of a Virtual University Consortium.'' Most noteworthy was, as mentioned above, our securing sponsorship from USD(AT&L) to fund research proposals selected from a nationwide call, or Broad Agency Announcement (BAA) (copy available at www.acquisitionresearch.org).'' We''re truly excited at the prospects of receiving innovative and cutting edge proposals from the top minds around the country.'' We trust that this new sponsorship will act like good seeds sown in fertile soil, yielding rich fruits of profitable acquisition research for many years to come.Naval Postgraduate School Acquisition Research ProgramApproved for public release; distribution is unlimited

Verifiable resilience in architectural reconfiguration

This thesis addresses the formal veri cation of a support infrastructure for resilient dynami- cally recon gurable systems. A component-based system, whose architectural con guration may change at runtime, is classed as dynamically recon gurable. Such systems require a support infrastructure for the control of recon gurations to provide resilience. The veri cation of such recon guration support increases the trust that developers and stakeholders may place on the system. The thesis de nes an architectural model of an infrastructure of services for the support of dynamic recon guration and takes a formal approach to the de nition and veri cation of one aspect of the infrastructure. The execution of recon guration policies in a recon guration infrastructure provides guidance to the architectural change to be enacted on a recon gurable system. These recon guration policies are often produced using a language with informal syntax and no formal semantics. Predicting properties of these policies governing recon guring systems has yet to be attempted. In this thesis, we de ne RPL { a recon guration policy language with a formal syntax and semantics. With the use of a case study, theories of RPL and an example policy are developed and the veri cation of key proof obligations and validation conjectures of policies expressed in RPL is demonstrated. The contribution of the thesis is two-fold. Firstly, the architectural de nition of a support infrastructure provides a lasting contribution in that it suggests a clear direction for future work in dynamic recon guration. Secondly, through the formal de nition of RPL and the veri cation of properties of policies, the thesis provides a basis for the use of formal veri cation in dynamic recon guration and, more speci cally, in policies for dynamic recon guration.EThOS - Electronic Theses Online ServiceEPSRC DIRC ProjectGBUnited Kingdo