Decentralized Orchestration of Open Services- Achieving High Scalability and Reliability with Continuation-Passing Messaging

The papers of this thesis are not available in Munin. Paper I: Yu, W.,Haque, A. A. M. “Decentralised web- services orchestration with continuation-passing messaging”. Available in International Journal of Web and Grid Services 2011, 7(3):304–330. Paper II: Haque, A. A. M., Yu, W.: “Peer-to-peer orchestration of web mashups”. Available in International Journal of Adaptive, Resilient and Autonomic Systems 2014, 5(3):40-60. Paper V: Haque, A. A. M., Yu, W.: “Decentralized and reliable orchestration of open services”. In:Service Computation 2014. International Academy, Research and Industry Association (IARIA) 2014 ISBN 978-1-61208-337-7.An ever-increasing number of web applications are providing open services to a wide range of applications. Whilst traditional centralized approaches to services orchestration are successful for enterprise service-oriented systems, they are subject to serious limitations for orchestrating the wider range of open services. Dealing with these limitations calls for decentralized approaches. However, decentralized approaches are themselves faced with a number of challenges, including the possibility of loss of dynamic run-time states that are spread over the distributed environment. This thesis presents a fully decentralized approach to orchestration of open services. Our flow-aware dynamic replication scheme supports both exceptional handling, failure of orchestration agents and recovers from fail situations. During execution, open services are conducted by a network of orchestration agents which collectively orchestrate open services using continuation-passing messaging. Our performance study showed that decentralized orchestration improves the scalability and enhances the reliability of open services. Our orchestration approach has a clear performance advantage over traditional centralized orchestration as well as over the current practice of web mashups where application servers themselves conduct the execution of the composition of open web services. Finally, in our empirical study we presented the overhead of the replication approach for services orchestration

Dynamic verification of mashups of service-oriented things through a mediation platform

The new Internet is evolving into the vision of the Internet of Things, where physical world entities are integrated into virtual world things. Things are expected to become active participants in business, information and social processes. Then, the Internet of Things could benefit from the Web Service architecture like today’s Web does; so Future service-oriented Internet things will offer their functionality via service-enabled interfaces. As demonstrated in previous work, there is a need of considering the behaviour of things to develop applications in a more rigorous way. We proposed a lightweight model for representing such behaviour based on the service-oriented paradigm and extending the standard DPWS profile to specify the (partial) order with which things can receive messages. To check whether a mashup of things respects the behaviour, specified at design-time, of composed things, we proposed a static verification. However, at run-time a thing may change its behaviour or receive requests from instances of different mashups. Then, it is required to check and detect dynamically possible invalid invocations provoked by the behaviour’s changes. In this work, we extend our static verification with an approach based on mediation techniques and complex event processing to detect and inhibit invalid invocations, checking that things only receive requests compatible with their behaviour. The solution automatically generates the required elements to perform run-time validation of invocations, and it may be extended to validate other issues. Here, we have also dealt with quality of service and temporal restrictions

A user-centric approach to service creation and delivery over next generation networks

Next Generation Networks (NGN) provide Telecommunications operators with the possibility to share their resources and infrastructure, facilitate the interoperability with other networks, and simplify and unify the management, operation and maintenance of service offerings, thus enabling the fast and cost-effective creation of new personal, broadband ubiquitous services. Unfortunately, service creation over NGN is far from the success of service creation in the Web, especially when it comes to Web 2.0. This paper presents a novel approach to service creation and delivery, with a platform that opens to non-technically skilled users the possibility to create, manage and share their own convergent (NGN-based and Web-based) services. To this end, the business approach to user-generated services is analyzed and the technological bases supporting the proposal are explained

An Effective End-User Development Approach Through Domain-Specific Mashups for Research Impact Evaluation

Over the last decade, there has been growing interest in the assessment of the performance of researchers, research groups, universities and even countries. The assessment of productivity is an instrument to select and promote personnel, assign research grants and measure the results of research projects. One particular assessment approach is bibliometrics i.e., the quantitative analysis of scientific publications through citation and content analysis. However, there is little consensus today on how research evaluation should be performed, and it is commonly acknowledged that the quantitative metrics available today are largely unsatisfactory. A number of different scientific data sources available on the Web (e.g., DBLP, Google Scholar) that are used for such analysis purposes. Taking data from these diverse sources, performing the analysis and visualizing results in different ways is not a trivial and straight forward task. Moreover, people involved in such evaluation processes are not always IT experts and hence not capable to crawl data sources, merge them and compute the needed evaluation procedures. The recent emergence of mashup tools has refueled research on end-user development, i.e., on enabling end-users without programming skills to produce their own applications. We believe that the heart of the problem is that it is impractical to design tools that are generic enough to cover a wide range of application domains, powerful enough to enable the specification of non-trivial logic, and simple enough to be actually accessible to non-programmers. This thesis presents a novel approach for an effective end-user development, specifically for non-programmers. That is, we introduce a domain-specific approach to mashups that "speaks the language of users"., i.e., that is aware of the terminology, concepts, rules, and conventions (the domain) the user is comfortable with.Comment: This PhD dissertation consists of 206 page

Design of a framework for automated service mashup creation and execution based on semantic reasoning

Instead of building self-contained silos, applications are being broken down in independent structures able to offer a scoped service using open communication standards and encoding. Nowadays there is no automatic environment for the construction of new mashups from these reusable services. At the same time the designer of the mashup needs to establish the actual locations for deployment of the different components. This paper introduces the development of a framework focusing on the dynamic creation and execution of service mashups. By enriching the available building blocks with semantic descriptions, new service mashups are automatically composed through the use of planning algorithms. The composed mashups are automatically deployed on the available resources making optimal use of bandwidth, storage and computing power of the network and server elements. The system is extended with dynamic recovery from resource and network failures. This enrichment of business components and services with semantics, reasoning, and distributed deployment is demonstrated by means of an e-shop use case

Enterprise Mashup Systems as Platform for Situational Applications - Benefits and Challenges in the Business Domain

Currently, several Enterprise 2.0 platforms are beginning to emerge. This paper introduces Enterprise Mashup technology as a means to improve IT alignment of individual work processes and changing business needs. Enterprise Mashups enable users to create customized applications to easily find and transform business information and functionalities, as well as collaboratively share pre-built Mashup applications. Therefore, the concept of Enterprise Mashups integrates Web 2.0 technologies and principles with well-established paradigms such as Enterprise Information Integration, Business Intelligence, and Business Process Management. Involved organizational key drivers, technical challenges and inhibitors are discussed to assess the potential business value and explain the emerging expansion of Mashup platforms in companies

Towards automated composition of convergent services: a survey

A convergent service is defined as a service that exploits the convergence of communication networks and at the same time takes advantage of features of the Web. Nowadays, building up a convergent service is not trivial, because although there are significant approaches that aim to automate the service composition at different levels in the Web and Telecom domains, selecting the most appropriate approach for specific case studies is complex due to the big amount of involved information and the lack of technical considerations. Thus, in this paper, we identify the relevant phases for convergent service composition and explore the existing approaches and their associated technologies for automating each phase. For each technology, the maturity and results are analysed, as well as the elements that must be considered prior to their application in real scenarios. Furthermore, we provide research directions related to the convergent service composition phases

A Framework for Collaborative Content Mashup with Pervasive Services

Kombineerides erinevaid teenuseid saavad mobiiltelefonid rahuldada paljusid tööstus ja ärivajadusi.Samas tuleb teenuste kombineerimise raames sisu õigesti tuvastamiseks ja tõlgendamiseks avastada ja töödelda suurt hulka andmeid. Kuna ainult ühe seadme kasu-tamine mingi ülesande lahendamiseks ei ole väga efektiivne on ühiste eesmärkide saa-vutamiseks soovitatav tööd mitme seadme vahel jagada. Pakume välja ja arendame üldraamistikku, mis toetab teenustele orienteeritud sisu segunemist ning laialt levinud teenuste loomise integreerimist, mis toimuks Business Process Execution Language (BPEL)-tuginevale kollaboratsioonile. Esitasime kollaboratsioonis seadmetele ressursi-säästliku teisaldamise plaani ja implementeerimise selle proof of concept'ina (kontseptsiooni tõestus). Hinnangu tulemused näitavad, et raamistik toetab kollaboratiivset ülesannete teisaldamise kava, mis vähendab mobiilsete seadete ressursside kasutamist.By composing pervasive services, mobile phones can support various industrial and commercial needs. However, the pervasive services composition involves discovering and processing a large amount of data in order to identify and interpret the content. Due to the limitation of the single device capability, it is advisable to collaborate with other devices via a wireless network to accomplish common goals. In this thesis, we propose and develop a generic framework that supports service-oriented content mashup and integrating pervasive services composition in the Business Process Execution Language (BPEL)-based collaboration. A resource-aware offloading scheme to collaborative devices has been proposed and implemented as a proof of concept. The evaluation results have shown that the framework supports collaborative task-offloading scheme that reduces the resource usage of mobile devices