Service-Driven Computing

Web services (WS) are becoming more and more popular nowadays and service-oriented architecture (SOA) have been widely used in the construction of information systems. But most of the SOA applications are not brand new and usually evolved from legacy systems. Our research group is building a service identification framework used for the SOA reengineering of existing large-scale information applications. Service capabilities have become an important issue we care about which are the actions performed or the information delivered by a service. But the semantic description for service capabilities has not been fully addressed in the current approach. In this paper, we analyze the contributions and limitations of current approach. In order to find the practical features of existing web services, we conducted a statistical study on more than four hundred WSDL documents collected from XMethods.net, Amazon and Google. Then we propose a new approach for Semantic Web Services description. Service capabilities are represented by informative entities and standard actions are specified for each informative entity.

The ability to dynamically compose autonomous services for optimally satisfying the requirements of different applications is one of the major advantages offered by the service-oriented computing (SOC) paradigm. A dynamic service composition implies that services requesters can be dynamically bound to most appropriate service providers that are available at runtime, in order to optimally satisfy the service requirements. At the same time, the autonomy of services involved in a composition means that the resulting composition may need to be adapted in response to changes in the service capabilities or requirements. Naturally, the infrastructure and technologies for providing runtime support for dynamic and adaptive composition of services form the backbone of the above process. In this chapter, we describe the Dino approach for providing the runtime support for dynamic and adaptive service composition. The Dino approach provides comprehensive support for all stages of a service composition life-cycle, namely: service discovery, selection, binding, delivery, monitoring and adaptation.

This paper describes how an infrastructure can be built for automating workflows in content production using a service oriented architecture (SOA). We fully adopted the SOA and the Business Process Management (BPM) vision in which stand-alone services provide modular functionality, service invocations are being orchestrated by a process engine, and human interaction is possible in the business processes through human tasks. We aimed at increased efficiency and control, shorter setup times, and increased flexibility. Our architecture is illustrated with a use case in which we automated a process that deals with the intake, review, transcoding and publishing of user-generated content.

In Service-Oriented Architecture (SOA), applications can be assembled by a set of existing distributed services spanning across organizations and platforms. SOA increases reuse and cooperation among services. Therefore, applications can be built in a rapid way with relatively low cost. With the increasing adoption of SOA solutions to application integration, the ability to compose services efficiently and effectively becomes more and more important. A lot of efforts have been devoted to service composition. Service composition integrates existing reusable services together as a process to fulfill business requirements, and exposes the process as a service (i.e., composite service). Specifically, a composition process involves the following five steps: 1. Specify business requirements: A requirement (e.g., purchase a book online) for composing services could be a declarative expression using formal or informal languages, an abstract process model (e.g., a business process model), or design models (e.g., UML diagrams). 2. Provide service description: Service description specifies the capability of services, such as inputs/outputs, exceptions, functional and non-functional description. 3. Discover relevant services: Service discovery is the process of locating a service that meets a certain searching criteria. For example, we search for an appropriate service to offer forecasting service. The searching criteria for the service discovery could be specified using keywords, such as weather forecast. 4. Generate composition process model: A composition process model contains a set of selected services, control flows and data flows among those services. Standards, such as BPEL (Business Process Execution Language), are used to formally specify process models. A business requirement usually cannot be fulfilled by a single service. Various services are integrated using composition process models. 5. Evaluate composition results: It is quite common that many returned services have the same or similar functionalities. It leads to more than one composition result to fulfill the business requirements. The different composition results can be evaluated to select the best one that meets the functional and nonfunctional requirements.

The increasing interest of researchers in service oriented architecture (SOA) for wireless sensor networks (WSNs) is opening new unexplored venues in the field of WSNs. In service oriented systems, services are configured and composed of various other services and thus perform complex tasks. In such composite services, the geospatial locations of services and their coverage is of vital importance as they signify the geospatial relevance of the service to the area of interest to the user. In this paper, we present a service-oriented system for WSNs that is capable of performing service configuration under geospatial and relevancy constraints. We present and evaluate "Cost Based Model (CBM)" and "Gain Based Model (GBM)" approaches to capture the relevancy of services hosted on WSN nodes in composite service configuration. The system is resilient to failures and can operate in manual or autonomous recovery modes. The system supports three service configuration methods namely, distributed, centralized and hybrid. Furthermore, we present a novel emulation mechanism for testing the performance of our proposed relevancy models and show that our system efficiently configures services.

Emerging business models such as digital ecosystems involving collaborative innovation, participatory decision-making and flexible organizational structures are set to significantly affect inter- and intra-enterprise structure and functionality. This has seen the appearance of increasingly complex Service-oriented Architecture (SOA) scenarios featuring various partnership levels, increased resilience and adaptation to tougher compliance regulations, more seamless integration with process layers, etc. This complexity has brought about the need to broaden the SOA paradigm, so as to include business, infrastructure and multi-layering, resulting in an evolved concept known as Service-Oriented Enterprise Architecture (SOEA). This paper aims to describe the way new business and technology paradigms continue to affect the new SOEA approach and how the inherently holistic Enterprise Architecture (EA) frameworks and related practices can support the emerging complex dynamic, multi-layered and value-chained service-based scenario.

Service Oriented Computing (SOC) is a computing paradigm broadly pushed by vendors, utilizing services to support the rapid development of distributed applications in heterogeneous environments. The visionary promise of SOC is a world of cooperating services being loosely coupled to flexibly create dynamic business processes and agile applications that may span organizations and computing platforms and can nevertheless adapt quickly and autonomously to changes of requirements or context. Consequently, the subject of Service Oriented Computing is vast and enormously complex, spanning many concepts and technologies that find their origins in diverse disciplines like Workflow Management Systems, Component Based Computing, "classical" Web applications, and Enterprise Application Integration (EAI) including Message Oriented Middleware. In addition, there is a strong need to merge technology with an understanding of business processes and organizational structures, a combination of recognizing an enterprise's pain points and the potential solutions that can be applied to correct them. Middleware, on the other hand, is defined by the ObjectWeb consortium as the software layer in a distributed computing system that lies between the operating system and the applications on each site of the system. Middleware is the enabling technology of system and enterprise application integration (EAI) and therefore it clearly and evidently plays a key role for SOC. While the immediate need of middleware support for Service Oriented Architectures (SOA) is evident, current approaches and solutions mostly fall short by primarily providing support for the EAI aspect of SOC only and do not sufficiently address composition support, service management and monitoring. Moreover, quality properties (in particular dependability and security) need to be addressed not only by interfacing and communication standards, but also in terms of integrated middleware support. But what makes these issues so different in a SOA setting? Why - for instance - is traditional middleware support for transaction processing different to transaction processing in SOA, reflecting different types of atomicity needs? One answer lies in the administrative heterogeneity, the loose coupling between coarsegrained operations and long-running interactions, high dynamicity, and the required flexibility during run-time. Recently, massive-scale and mobility were added to the challenges for Middleware for SOC. However, loose coupling is not always the best approach to solve a particular problem. In order to temporarily allow for a stronger (traditional) form of coupling (like group membership agreement or atomic transaction), the middleware also has to provide explicit and configurable means to change between different strengths of coupling and various communication paradigms. This will enable servicebased applications to take the best from both worlds by dynamically adjusting the interactions between the composed services. The highly dynamic modularity and need for flexible integration of services (e.g. Web service implementations) may require new middleware architectures, protocols, and services. These considerations also lead to the question to what extent service-orientation at the middleware layer itself is beneficial (or not). Recently emerging "Middleware as service" offerings, from providers like Amazon or from the open source community, support this trend towards "infrastructure services" that can be purchased and consumed over the Internet. However, this model may not be suitable for all kinds of middleware functions, including those addressing dependability (availability, reliability, integrity, safety, maintainability). Providing end-to-end properties and addressing cross-cutting concerns in a crossorganizational SOA is a particular challenge and the limits and benefits thereof have still to be investigated.

Service-Oriented Architecture (SOA) is an architectural concept to build software which emphasizes the use of services and comprises design principles. Research on this paper implements SOA design principles in the development of Animal Video Encyclopedia and Plant Video Encyclopedia. By implementing SOA, this paper would like to see if SOA affects the number of Function Points in the development of a software solution. Function Point numbers which are the result of Function Point Analysis (FPA) calculation have been widely used in software industry to measure the size of an application based on functionalities from user’s perspective. This paper uses FPA method to count the Function Points between both Animal and Plant Video Encyclodias solution implementing SOA and Animal and Plant Video Encyclopedias solution that does not implement SOA. Function Points from both solutions are then compared and analyzed based on the implementation of SOA design principles. Results show that numbers of Function Points of the solution implementing SOA appear to be smaller than the number of Function Points of the solution which is not implementing SOA.

As the capability of an individual Web service is limited, it's necessary to create new functionalities with existing Web services. Web services composition is the ability to create a new value-added service by incorporating some existing Web services together. An important challenge for Web services composition is how to ensure the correctness and reliability of the WS-BPEL (Web services business process execution language) process and the composition. A graphical and formal modeling tool suitable for solving this problem is CPN (Colored Petri net), which provides formal semantics and a number of analysis techniques for modeling and verifying web services composition. This paper proposes a CPN-based model for web services composition, describes how to translate WS-BPEL to CPN model, and discusses the analysis and verification of services composition. The model enables efficient composition of Web services and validates the correctness of composition by formal verification.

We illustrate the addictions and mental health service use of American Indian adolescents. Interviews concerning mental health need and service configurations with 401 Southwestern American Indian (AI) youth used questions from the Diagnostic Interview Schedule (DIS) and the Service Assessment for Children and Adolescents (SACA). Seventy-nine percent had mental health or addiction problems, with half meeting criteria for at least one diagnosis. One in 4 youth met criteria for drug dependence'abuse or conduct disorder, 1 in 5 for depression, and 1 in 8 for alcohol dependence'abuse. Most youth were helped by a combination of providers. Youth meeting more diagnostic criteria were increasingly likely to use service configurations with adults, nonspecialist professionals, and specialists, respectively. Regardless of disorder, youth were least likely to use configurations with traditional healers or specialists and there was little difference in rates of use between the two. The lack of services from specialist providers was potentially offset by use of an extensive range of informal adults, nonspecialist professionals, and peers. Since informal helpers, peers, and nonspecialist providers, but not specialists, are providing the bulk of services they must be given support and skills so they can function effectively.

With the advent of newly introduced programming models like Feature-Oriented Programming (FOP), we feel that it will be more flexible to include the new service invocation function into the service providing server as a Feature Module for the self-adaptive distributed systems. A composite design patterns shows a synergy that makes the composition more than just the sum of its parts which leads to ready-made software architectures. In this paper we describe the amalgamation of Visitor and Case-Based Reasoning Design Patterns to the development of the Service Invocation and Web Services Composition through SOA with the help of JWS technologies and FOP. As far as we know, there are no studies on composition of design patterns for self adaptive distributed computing domain. We have provided with the sample code developed for the application and simple UML class diagram is used to describe the architecture.

Engineering services in the framework of an service-oriented architecture (SOA) is complex and open to mistakes if a rigorous approach is not taken. Combining SOA with features to support dynamic service discovery, management and binding, increase the chances that an architecture configuration has been incorrectly specified. To facilitate service engineers designing and implementing service systems we introduced the notion of service modes, that at design time provide an abstraction of service configurations given particular requirements for runtime. This paper describes how behaviour protocols are included in these configurations and how properties of combined architecture and behaviour models can be used to perform some useful analysis to assure dynamic service architecture configurations are safer and more resilient to incompatibilities. The modelling and analysis techniques are supported by an implementation in the LTSA WS-Engineer, a comprehensive integrated tool suite for verification and validation of service compositions.

The Service Oriented Architecture (SOA, [1]) can be applied to enterprise integration. It creates an Internet of services for enterprises. Service science [2] defines services in term of value propositions of enterprises to customers. Both service science and the Internet of services require a form of mediation between customer requirements and service capabilities like for instance identified in [3]. However, mediation is not yet automated, thus can not be applied real time. Furthermore, many business areas already have agreement on semantics and interaction sequencing based on existing business documents, thus, mediation is not always required for a certain business area. This paper presents an ontology to support business services (Ontology Web Language (OWL), [18]). The concepts shared at business level are based on existing approaches like Resource, Event, Agent used for auditing and control [4] and builds upon service frameworks like OWL-S [13]. The ontology will be specialized to logistics and compared with other approaches that might be applied to enterprise integration.

The aim of this study was to examine psychosocial factors associated with military fitness class, classified as capability of service, vs. temporary or permanent exemption from service. Participants were 2,340 (80% of the original sample) Finnish 18-year-old men at call-up for obligatory military service who filled in the Young Adult Self-Report (YASR) questionnaire. Temporary exemption from military service was independently associated with the YASR total problem score, externalizing and internalizing problems, excessive alcohol use, drug use, problems with peers and family, and mental health service use. Permanent exemption was independently associated with problems with peers and family. The YASR is a potential selection tool to be used at call-up. Temporary exemption was more strongly associated with psychosocial problems than permanent exemption. Because of the high level of psychological problems among those temporarily exempted, the call-up situation offers a unique opportunity to identify those with problem behaviour and risk of marginalization.

In this article we address the integration of functional models with non-functional models in the context of service-oriented enterprise architecture. Starting from the observation that current approaches to model-driven development have a strong focus on functionality, we argue the necessity of including non-functional aspects as early as possible in the service design process. We distinguish two modelling spaces, the design space and the analysis space, which can be integrated by means of model transformations. Quantitative results obtained in the analysis space, using special-purpose analysis techniques, can be related back to the design models by means of a reverse transformation. This provides a framework for incorporating non-functional analysis into methodological support for e-service development. While, for detailed design models, performance analysis is more or less covered by existing techniques, there is still a gap at the architectural overview level. Therefore, we propose an approach for performance analysis of layered, service-oriented architecture models, which consists of two phases: a ‘‘top-down’’ propagation of workload parameters, and a “bottom-up’’ propagation of performance or cost measures. By means of an example, we demonstrate the application of the approach and show that a seamless integration with detailed performance analysis methods (e.g., queueing analysis) can be achieved.