Applying OMG D&C Specification and ECA Rules for Autonomous Distributed Component-based Systems

Manual administration of complex distributed applications is almost impossible to achieve. On one side, work in autonomic computing focuses on systems that are able to maintain themselves, driven by high-level policies. Such a selfadministration relies on the concept of a control loop. On the other side, modeling is currently used to ease design of complex distributed systems. Nevertheless, at runtime, models remain useless, because they are decoupled from the running system which is subject to dynamic changes. The autonomic computing control loop involves an abstract representation of the system used to analyze the situation and to adapt the application properly. Our proposition, named Distributed Autonomous Component-based ARchitectures (Dacar), introduces models in the control loop. Using adequate models into the control loop, it is possible to design both the distributed systems and their evolution policies, and to execute them. The metamodel suggested in our work mixes both OMG Deployment and Configuration specification and the Event-Condition-Action (ECA) metamodels. This paper treats the different concerns that are present in the control loop and focuses on the concepts of the metamodel that are needed to express entities of the control loop. It also gives an overview of the current Dacar prototype and illustrated it on an ubiquitous application example

Towards Model-Driven Validation of Autonomic Software Systems in Open Distributed Environments

New distributed systems are running onto fluctuating environments (e.g. ambient or grid computing). These fluctuations must be taken into account when deploying these systems. Autonomic computing aims at realizing programs that implement self-adaptation behaviour. Unfortunately in practice, these programs are not often statically validated, and their execution can lead to emergent undesirable behaviour. In this paper, we argue that static validation is mandatory for large autonomic distributed systems. We identify two kinds of validation that are relevant and crucial when deploying such systems. These validations affect the deployment procedures of software composing a system, as well as the autonomic policies of this system. Using our Dacar model-based framework for deploying autonomic software distributed architectures, we show how we tackle the problem of static validation of autonomic distributed system

A Change Execution System for Enterprise Services with Compensation Support

Modern enterprises rely on a distributed IT infrastructure to execute their business processes, adopting Service Oriented Architectures in order to improve the flexibility and ease of adaptation of their functions. Nowadays this is a vital characteristic, as the increased competition forces companies to continuously evolve and adapt. SOA applications must be supported by management and deployment systems, which have to continuously apply modifications to the distributed infrastructure. This article presents a modelbased solution for automatically applying change plans to heterogeneous enterprise managed environments. The proposed solution uses models which describe in an abstract language the changes that need to be applied to the environment, and executes all the required operations to the specific managed elements. Also, to ensure that the environment ends in a stable state, compensation for previously executed operations is supported. The validation results from a case study taken from the banking domain are also presented here

Incorporating the elements of the mase methodology into agent open

Enterprise-wide, web-based systems can be assisted in their construction by the use of agents and an agent-oriented methodology. As part of an extensive research programme to create such an AO methodology by combining the benefits of method engineering and existing object-oriented frameworks (notably the OPF), we have analysed here contributions to the OPF repository of process components from the MASE agent-oriented methodology, identifying three new Tasks, one additional Technique and two new Work Products

A Systematic Approach to Constructing Incremental Topology Control Algorithms Using Graph Transformation

Communication networks form the backbone of our society. Topology control algorithms optimize the topology of such communication networks. Due to the importance of communication networks, a topology control algorithm should guarantee certain required consistency properties (e.g., connectivity of the topology), while achieving desired optimization properties (e.g., a bounded number of neighbors). Real-world topologies are dynamic (e.g., because nodes join, leave, or move within the network), which requires topology control algorithms to operate in an incremental way, i.e., based on the recently introduced modifications of a topology. Visual programming and specification languages are a proven means for specifying the structure as well as consistency and optimization properties of topologies. In this paper, we present a novel methodology, based on a visual graph transformation and graph constraint language, for developing incremental topology control algorithms that are guaranteed to fulfill a set of specified consistency and optimization constraints. More specifically, we model the possible modifications of a topology control algorithm and the environment using graph transformation rules, and we describe consistency and optimization properties using graph constraints. On this basis, we apply and extend a well-known constructive approach to derive refined graph transformation rules that preserve these graph constraints. We apply our methodology to re-engineer an established topology control algorithm, kTC, and evaluate it in a network simulation study to show the practical applicability of our approachComment: This document corresponds to the accepted manuscript of the referenced journal articl

Towards Model-Driven Validation of Autonomic Software Systems in Open Distributed Environments

New distributed systems are running onto fluctuating environments (e.g. ambient or grid computing). These fluctuations must be taken into account when deploying these systems. Autonomic computing aims at realizing programs that implement self-adaptation behaviour. Unfortunately in practice, these programs are not often statically validated, and their execution can lead to emergent undesirable behaviour. In this paper, we argue that static validation is mandatory for large autonomic distributed systems. We identify two kinds of validation that are relevant and crucial when deploying such systems. These validations affect the deployment procedures of software composing a system, as well as the autonomic policies of this system. Using our Dacar model-based framework for deploying autonomic software distributed architectures, we show how we tackle the problem of static validation of autonomic distributed system

Autonomic Pervasive Applications Driven by Abstract Specifications

Conference in conjunction with ICAC 2012 (International Conference on Autonomic Computing)International audiencePervasive application architectures present stringent requirements that make their development especially hard. In particular, they need to be flexible in order to cope with dynamism in different forms (e.g. service and data providers and consumers). The current trend to build applications out of remote services makes the availability of constituent application components inherently dynamic. Developers can no longer assume that applications are static after development or at run time. Unfortunately, developing applications that are able to cope with dynamism is very complex.Existing development approaches do not provide explicit support for managing dynamism. In this paper we describe Rondo, a tool suite for designing pervasive applications. More specifically, we present our propositions in pervasive application specification, which borrows concepts from service-oriented component assembly, model-driven engineering (MDE) and continuous deployment, resulting in a more flexible approach than traditional application definitions. Then the capabilities of our application model are demonstrated with an example application scenario designed using our approach

An Optimized, Data Distribution Service-Based Solution for Reliable Data Exchange Among Autonomous Underwater Vehicles

Major challenges are presented when managing a large number of heterogeneous vehicles that have to communicate underwater in order to complete a global mission in a cooperative manner. In this kind of application domain, sending data through the environment presents issues that surpass the ones found in other overwater, distributed, cyber-physical systems (i.e., low bandwidth, unreliable transport medium, data representation and hardware high heterogeneity). This manuscript presents a Publish/Subscribe-based semantic middleware solution for unreliable scenarios and vehicle interoperability across cooperative and heterogeneous autonomous vehicles. The middleware relies on different iterations of the Data Distribution Service (DDS) software standard and their combined work between autonomous maritime vehicles and a control entity. It also uses several components with different functionalities deemed as mandatory for a semantic middleware architecture oriented to maritime operations (device and service registration, context awareness, access to the application layer) where other technologies are also interweaved with middleware (wireless communications, acoustic networks). Implementation details and test results, both in a laboratory and a deployment scenario, have been provided as a way to assess the quality of the system and its satisfactory performanceEuropean Commission H2020. SWARMs European project (Smart and Networking Underwater Robots in Cooperation Meshes), under Grant Agreement No. 662107-SWARMs-ECSEL-2014-1, partially supported by the ECSEL JU, the Spanish Ministry of Economy and Competitiveness (Ref: PCIN-2014-022-C02-02)