Secure data sharing and processing in heterogeneous clouds

The extensive cloud adoption among the European Public Sector Players empowered them to own and operate a range of cloud infrastructures. These deployments vary both in the size and capabilities, as well as in the range of employed technologies and processes. The public sector, however, lacks the necessary technology to enable effective, interoperable and secure integration of a multitude of its computing clouds and services. In this work we focus on the federation of private clouds and the approaches that enable secure data sharing and processing among the collaborating infrastructures and services of public entities. We investigate the aspects of access control, data and security policy languages, as well as cryptographic approaches that enable fine-grained security and data processing in semi-trusted environments. We identify the main challenges and frame the future work that serve as an enabler of interoperability among heterogeneous infrastructures and services. Our goal is to enable both security and legal conformance as well as to facilitate transparency, privacy and effectivity of private cloud federations for the public sector needs. © 2015 The Authors

Interaction protocols for cross-organisational workflows

Workflow technologies are widely used in industry and commerce to assist in the specification, execution and completion of well defined processes within organisations. As industrial and commercial relations have evolved, based on advances on information and communications technologies, cross-organisational workflow integration has become an important issue. Since organisations can have very different workflows, the creation of compatible workflows so that organisations can collaborate and/or carry out mutual transactions automatically in an integrated fashion can be a very complex and time consuming process. As a consequence, the development of technologies to support the creation and execution of compatible workflows is a most relevant issue. In the present article we introduce the JamSession coordination platform as a tool to implement cross-organisational workflow integration. JamSession is declarative and based on algebraic specification methods, and therefore workflow integration implemented using this platform can profit from formal behavioural analysis, based on which desired features and properties can be verified and/or obtained

Diagnosis of Errors in Stalled Inter-Organizational Workflow Processes

Fault-tolerant inter-organizational workflow processes help participant organizations efficiently complete their business activities and operations without extended delays. The stalling of inter-organizational workflow processes is a common hurdle that causes organizations immense losses and operational difficulties. The complexity of software requirements, incapability of workflow systems to properly handle exceptions, and inadequate process modeling are the leading causes of errors in the workflow processes. The dissertation effort is essentially about diagnosing errors in stalled inter-organizational workflow processes. The goals and objectives of this dissertation were achieved by designing a fault-tolerant software architecture of workflow system’s components/modules (i.e., workflow process designer, workflow engine, workflow monitoring, workflow administrative panel, service integration, workflow client) relevant to exception handling and troubleshooting. The complexity and improper implementation of software requirements were handled by building a framework of guiding principles and the best practices for modeling and designing inter-organizational workflow processes. Theoretical and empirical/experimental research methodologies were used to find the root causes of errors in stalled workflow processes. Error detection and diagnosis are critical steps that can be further used to design a strategy to resolve the stalled processes. Diagnosis of errors in stalled workflow processes was in scope, but the resolution of stalled workflow process was out of the scope in this dissertation. The software architecture facilitated automatic and semi-automatic diagnostics of errors in stalled workflow processes from real-time and historical perspectives. The empirical/experimental study was justified by creating state-of-the-art inter-organizational workflow processes using an API-based workflow system, a low code workflow automation platform, a supported high-level programming language, and a storage system. The empirical/experimental measurements and dissertation goals were explained by collecting, analyzing, and interpreting the workflow data. The methodology was evaluated based on its ability to diagnose errors successfully (i.e., identifying the root cause) in stalled processes caused by web service failures in the inter-organizational workflow processes. Fourteen datasets were created to analyze, verify, and validate hypotheses and the software architecture. Amongst fourteen datasets, seven datasets were created for end-to-end IOWF process scenarios, including IOWF web service consumption, and seven datasets were for IOWF web service alone. The results of data analysis strongly supported and validated the software architecture and hypotheses. The guiding principles and the best practices of workflow process modeling and designing conclude opportunities to prevent processes from getting stalled. The outcome of the dissertation, i.e., diagnosis of errors in stalled inter-organization processes, can be utilized to resolve these stalled processes

Size Matters: Microservices Research and Applications

In this chapter we offer an overview of microservices providing the introductory information that a reader should know before continuing reading this book. We introduce the idea of microservices and we discuss some of the current research challenges and real-life software applications where the microservice paradigm play a key role. We have identified a set of areas where both researcher and developer can propose new ideas and technical solutions.Comment: arXiv admin note: text overlap with arXiv:1706.0735

A Taxonomy of Data Grids for Distributed Data Sharing, Management and Processing

Data Grids have been adopted as the platform for scientific communities that need to share, access, transport, process and manage large data collections distributed worldwide. They combine high-end computing technologies with high-performance networking and wide-area storage management techniques. In this paper, we discuss the key concepts behind Data Grids and compare them with other data sharing and distribution paradigms such as content delivery networks, peer-to-peer networks and distributed databases. We then provide comprehensive taxonomies that cover various aspects of architecture, data transportation, data replication and resource allocation and scheduling. Finally, we map the proposed taxonomy to various Data Grid systems not only to validate the taxonomy but also to identify areas for future exploration. Through this taxonomy, we aim to categorise existing systems to better understand their goals and their methodology. This would help evaluate their applicability for solving similar problems. This taxonomy also provides a "gap analysis" of this area through which researchers can potentially identify new issues for investigation. Finally, we hope that the proposed taxonomy and mapping also helps to provide an easy way for new practitioners to understand this complex area of research.Comment: 46 pages, 16 figures, Technical Repor

Service-Oriented Process Models in Telecommunication Business

The thesis concentrates on to evaluate challenges in the business process management and the need for Service-oriented process models in telecommunication business to alleviate the integration work efforts and to reduce total costs of ownership. The business aspect concentrates on operations and business support systems which are tailored for communication service providers. Business processes should be designed in conformance with TeleManagement Forum's integrated business architecture framework. The thesis rationalizes the need to transform organizations and their way of working from vertical silos to horizontal layers and to understand transformational efforts which are needed to adopt a new strategy. Furthermore, the thesis introduces service characterizations and goes deeper into technical requirements that a service compliant middleware system needs to support. At the end of the thesis Nokia Siemens Networks proprietary approach – Process Automation Enabling Suite is introduced, and finally the thesis performs two case studies. The first one is Nokia Siemens Networks proprietary survey which highlights the importance of customer experience management and the second one is an overall research study whose results have been derived from other public surveys covering application integration efforts

A programming system for process coordination in virtual organisations

PhD thesisDistributed business applications are increasingly being constructed by composing them from services provided by various online businesses. Typically, this leads to trading partners coming together to form virtual organizations (VOs). Each member of a VO maintains their autonomy, except with respect to their agreed goals. The structure of the Virtual Organisation may contain one dominant organisation who dictates the method of achieving the goals or the members may be considered peers of equal importance. The goals of VOs can be defined by the shared global business processes they contain. To be able to execute these business processes, VOs require a flexible enactment model as there may be no single ‘owner’ of the business process and therefore no natural place to enact the business processes. One solution is centralised enactment using a trusted third party, but in some cases this may not be acceptable (for instance because of security reasons). This thesis will present a programming system that allows centralised as well as distributed enactment where each organisation enacts part of the business process. To achieve distributed enactment we must address the problem of specifying the business process in a manner that is amenable to distribution. The first contribution of this thesis is the presentation of the Task Model, a set of languages and notations for describing workflows that can be enacted in a centralised or decentralised manner. The business processes that we specify will coordinate the services that each organisation owns. The second contribution of this thesis is the presentation of a method of describing the observable behaviour of these services. The language we present, SSDL, provides a flexible and extensible way of describing the messaging behaviour of Web Services. We present a method for checking that a set of services described in SSDL are compatible with each other and also that a workflow interacts with a service in the desired manner. The final contribution of this thesis is the presentation of an abstract architecture and prototype implementation of a decentralised workflow engine. The prototype is able to enact workflows described in the Task Model notation in either a centralised or decentralised scenario

Microservice API Evolution in Practice: A Study on Strategies and Challenges

Nowadays, many companies design and develop their software systems as a set of loosely coupled microservices that communicate via their Application Programming Interfaces (APIs). While the loose coupling improves maintainability, scalability, and fault tolerance, it poses new challenges to the API evolution process. Related works identified communication and integration as major API evolution challenges but did not provide the underlying reasons and research directions to mitigate them. In this paper, we aim to identify microservice API evolution strategies and challenges in practice and gain a broader perspective of their relationships. We conducted 17 semi-structured interviews with developers, architects, and managers in 11 companies and analyzed the interviews with open coding used in grounded theory. In total, we identified six strategies and six challenges for REpresentational State Transfer (REST) and event-driven communication via message brokers. The strategies mainly focus on API backward compatibility, versioning, and close collaboration between teams. The challenges include change impact analysis efforts, ineffective communication of changes, and consumer reliance on outdated versions, leading to API design degradation. We defined two important problems in microservice API evolution resulting from the challenges and their coping strategies: tight organizational coupling and consumer lock-in. To mitigate these two problems, we propose automating the change impact analysis and investigating effective communication of changes as open research directions

Dynamic Multilevel Workflow Management Concept for Industrial IoT Systems

Workflow management is implemented in manufacturing at many levels. The nature of processes variesat each level, hindering the use of a standard modeling orimplementation solution. The creation of a flexible workflow management framework that overarches the heterogeneous business process levels is challenging. Still, one of the promisesof the Industry 4.0 initiative is precisely this: to provideeasy-to-use models and solutions that enable efficient execution of enterprise targets. By addressing this challenge, this articleproposes a workflow execution model that integrates information and control flows of these levels while keeping their hierarchy. The overall model builds on the business process model andnotation (BPMN) for modeling at the enterprise level and recipemodeling based on colored Petri net (CPN) at the production level. Models produced with both alternatives are implemented and executed in a framework supported by an enterprise servicebus (ESB). Loosely coupled, late-bound system elements are connected through the arrowhead framework, which is builtupon the service-oriented architecture (SOA) concept. To proveits feasibility, this article presents the practical application ofthe model via an automotive production scenario