Service Composition Tools Research Articles

From Service Composition to Mashup Editor: A Multiperspective Taxonomy

Service-oriented computing has become a popular area of research, with a particular focus on service composition. There have been many developments in this field, such as new techniques for data engineering in service description languages, protocols for publication and discovery, the optimization of service selection and scheduling, and the deployment and monitoring of composed services. However, this diversity of approaches and methodologies can make it challenging to navigate between different proposed solutions and identify research gaps. In order to provide a clearer understanding of this body of work, this paper presents a comprehensive framework for the taxonomy of service composition approaches, methodologies, and tools. This framework proposes a structured view of different perspectives, such as formal, semantic, and automatic approaches, with a particular focus on the end-user’s perspective and tools such as Mashups.

Non-Programmers Composing Software Services: A Confirmatory Study of the Mental Models and Design Challenges

Ordinary web users can now create and publish online content. They even venture into “mashups,” integrating information from different sources into a composite information-providing web service. This is a non-trivial design task, which falls into the area of end-user development when the ordinary users who perform it do not have programming education. In this article, we investigate the service design strategies of 12 such ordinary users and compare them against the baseline of 12 programmers. In our think-aloud study, users completed two contrasting types of tasks involved in developing service-based applications: (a) manual service composition and (b) parametric design using templates with a high degree of software support (or assisted composition). These service composition tasks were chosen to differ in respect to the level of user support provided by the tool. Our findings show that non-programmers liked, more than programmers, the template-based parametric design and did not find the tool assistance as constraining as the programmers did. The difficulty of design involved in manual service composition and the absence of user guidance hindered non-programmers in expressing and implementing accurate design solutions. The differences in the mental models and needs of non-programmers are established to be in stark contrast to those of programmers. We used the details of our findings to propose specialized design recommendations for service composition tools aligned with the profiles of their target users.

Building IoT Services for Aging in Place Using Standard-Based IoT Platforms and Heterogeneous IoT Products.

An aging population and human longevity is a global trend. Many developed countries are struggling with the yearly increasing healthcare cost that dominantly affects their economy. At the same time, people living with old adults suffering from a progressive brain disorder such as Alzheimer’s disease are enduring even more stress and depression than those patients while caring for them. Accordingly, seniors’ ability to live independently and comfortably in their current home for as long as possible has been crucial to reduce the societal cost for caregiving and thus give family members peace of mind, called ‘aging in place’ (AIP). In this paper we present a way of building AIP services using standard-based IoT platforms and heterogeneous IoT products. An AIP service platform is designed and created by combining previous standard-based IoT platforms in a collaborative way. A service composition tool is also created that allows people to create AIP services in an efficient way. To show practical usability of our proposed system, we choose a service scenario for medication compliance and implement a prototype service which could give old adults medication reminder appropriately at the right time (i.e., when it is time to need to take pills) through light and speaker at home but also wrist band and smartphone even outside the home.

Web Service Composition

Web services are a consolidated reality of the modern Web with tremendous, increasing impact on everyday computing tasks. They turned the Web into the largest, most accepted, and most vivid distributed computing platform ever. Yet, the use and integration of Web services into composite services or applications, which is a highly sensible and conceptually non-trivial task, is still not unleashing its full magnitude of power. A consolidated analysis framework that advances the fundamental understanding of Web service composition building blocks in terms of concepts, models, languages, productivity support techniques, and tools is required. This framework is necessary to enable effective exploration, understanding, assessing, comparing, and selecting service composition models, languages, techniques, platforms, and tools. This article establishes such a framework and reviews the state of the art in service composition from an unprecedented, holistic perspective.

Towards end-user development of REST client applications on smartphones

HTML5 can be used to develop client applications by composing REST web services within the context of Web 2.0. However, the possibility of implementing cross-platform smartphone applications with REST services needs to be studied. Accordingly, we developed a REST-based cross-platform application with PhoneGap. The application was deployed on the Android, Windows Phone, and iOS platforms; subsequently we evaluated its usability. We observed that REST-based cross-platform smartphone applications can be implemented with HTML5 and PhoneGap, which can be scaled-up into a REST service composition tool. Moreover, the application’s usability remains unaffected on the native platforms and adaptation required only minimal effort.

Consumerized and peer-tutored service composition

With continued development towards the Internet of Things, services are making their way from enterprise solutions to our offices and homes. This process is a major driving force in consumerization of IT, because sustainable application development at this scale will not be possible without direct involvement and innovation from consumers themselves. In this paper, we present our work on consumerization of service composition tools. First, we describe how consumer-facing services can be presented in a usable and intuitive way. Then, combining social computing with machine intelligence, we define a recommender system that supports consumers in sharing their knowledge and creativity in peer-tutored service composition, thus empowering consumers to create their own applications. This system recommends consumers with the required service composition knowledge based on mining procedural knowledge stored in previously defined compositions. Once such a group of consumers is identified, social computing tools are used to allow them to share this knowledge with their peers. To demonstrate the effectiveness of this peer-tutored service composition model, we performed consumer satisfaction studies on our consumerized service composition tool Geppeto, which we extended with the described recommender system. Results show significant improvements in service composition in terms of performance and quality of experience.

Establishing requirements for End-user Service Composition tools

End-user Service Composition (EUSC) is defined as service composition where the person who creates the composite service also uses it. We derived requirements for EUSC tools using a custom method based on the scenario-based requirements analysis method. Ten participants were given scenarios, a demonstrator application and examples of EUSC tools before being interviewed. Analysing their responses, we elicited 139 requirements across topics including service “types” (e.g. pervasive services), composition flow (i.e. control/data flow) and the use of templates in composition. This is the first published work to have used a robust requirements analysis method in EUSC, adapted specifically to take account of prior work on EUSC. Some of our requirements validate those found in prior research or current EUSC tools but many are unique to our findings. The requirements found in this work inform and inspire the development of future EUSC tools, and the methodology is easily adapted for application in other domains.

An experimental service composition tool for media-centric networked applications

In order to explore diverse types of media-centric service composition in real environments, we have built a service-oriented testbed named as FIRST@PC (Future Internet Research on Sustainable Testbed based on PC). FIRST@PC targets a flexible and cost-effective testing environment where media-centric service compositions are flexibly realized on top of computing/networking resources. In this paper we design and implement an OMX (Open Media eXperiment for service composition) experiment control tool to support media-centric service composition. By following the SOC (service-oriented computing) paradigm, the OMX tool assists experimenters to flexibly integrate computing and networking services. To explore the possibility of media-centric service composition, we also prototype the FIRST@PC testbed consisting of multimedia computing and networking devices. The implemented OMX tool is verified by an HD media service composition scenario run on this prototyped testbed.

QoS-Aware Automatic Service Composition: A Graph View

In the research of service composition, it demands efficient algorithms that not only retrieve correct service compositions automatically from thousands of services but also satisfy the quality requirements of different service users. However, most approaches treat these two aspects as two separate problems, automatic service composition and service selection. Although the latest researches realize the restriction of this separate view and some specific methods are proposed, they still suffer from serious limitations in scalability and accuracy when addressing both requirements simultaneously. In order to cope with these limitations and efficiently solve the combined problem which is known as QoS-aware or QoS-driven automatic service composition problem, we propose a new graph search problem, single-source optimal directed acyclic graphs (DAGs), for the first time. This novel single-source optimal DAGs (SSOD) problem is similar to, but more general than the classical single-source shortest paths (SSSP) problem. In this paper, a new graph model of SSOD problem is proposed and a Sim-Dijkstra algorithm is presented to address the SSOD problem with the time complexity of O(nlog n + m) (n and m are the number of nodes and edges in the graph respectively), and the proofs of its soundness. It is also directly applied to solve the QoS-aware automatic service composition problem, and a service composition tool named QSynth is implemented. Evaluations show that Sim-Dijkstra algorithm achieves superior scalability and efficiency with respect to a large variety of composition scenarios, even more efficient than Our worklist algorithm that won the performance championship of Web Services Challenge 2009.

Ontology-driven service composition for end-users

Current service composition techniques and tools are mainly designed for use by Service-Oriented Architecture (SOA) professionals to solve business problems. Little attention has been paid to allowing end-users without sufficient service composition skills to compose services and integrate SOA solutions into their online experience to fulfill their daily activities. To shelter end-users from the complexity of service composition, we propose an approach which can compose services on the fly to meet the situational needs of end-users. We present a tag-based service description schema which allows non-IT professional users to easily understand the description of services and add their own descriptions using descriptive tags. Instead of requiring end-users to specify detailed steps for composition, the end-users only need to describe their goals using a few keywords. Our approach expands the meaning of a user's goal using ontologies then derives a group of keywords to discover services in order to fulfill the goal. A prototype is developed as a proof of concept to show that our approach enables end-users to discover and compose services easily. We conduct a case study to evaluate the effectiveness of our approach that eases end-users to compose services without the knowledge of SOA technologies. The results of our case study show that our approach can effectively generate ad-hoc processes and discover services with relatively high precision and recall.

Automated composition of Web services via planning in asynchronous domains

The service-oriented paradigm promises a novel degree of interoperability between business processes, and is leading to a major shift in way distributed applications are designed and realized. While novel and more powerful services can be obtained, in such setting, by suitably orchestrating existing ones, manually developing such orchestrations is highly demanding, time-consuming and error-prone. Providing automated service composition tools is therefore essential to reduce the time to market of services, and ultimately to successfully enact the service-oriented approach. In this paper, we show that such tools can be realized based on the adoption and extension of powerful AI planning techniques, taking the “planning via model-checking” approach as a stepping stone. In this respect, this paper summarizes and substantially extends a research line that started early in this decade and has continued till now. Specifically, this work provides three key contributions. First, we describe a novel planning framework for the automated composition of Web services, which can handle services specified and implemented using industrial standard languages for business processes modeling and execution, like ws-bpel. Since these languages describe stateful Web services that rely on asynchronous communication primitives, a distinctive aspect of the presented framework is its ability to model and solve planning problems for asynchronous domains. Second, we formally spell out the theory underlying the framework, and provide algorithms to solve service composition in such framework, proving their correctness and completeness. The presented algorithms significantly extend state-of-the-art techniques for planning under uncertainty, by allowing the combination of asynchronous domains according to behavioral requirements. Third, we provide and discuss an implementation of the approach, and report extensive experimental results which demonstrate its ability to scale up to significant cases for which the manual development of ws-bpel composed services is far from trivial and time consuming.

Configurable Composition and Adaptive Provisioning of Web Services

Web services composition has been an active research area over the last few years. However, the technology is still not mature yet and several research issues need to be addressed. In this paper, we describe the design of CCAP, a system that provides tools for adaptive service composition and provisioning. We introduce a composition model where service context and exceptions are configurable to accommodate needs of different users. This allows for reusability of a service in different contexts and achieves a level of adaptiveness and contextualization without recoding and recompiling of the overall composed services. The execution semantics of the adaptive composite service is provided by an event-driven model. This execution model is based on Linda Tuple Spaces and supports real-time and asynchronous communication between services. Three core services, coordination service, context service, and event service, are implemented to automatically schedule and execute the component services, and adapt to user configured exceptions and contexts at run time. The proposed system provides an efficient and flexible support for specifying, deploying, and accessing adaptive composite services. We demonstrate the benefits of our system by conducting usability and performance studies.

End-User Service Computing: Spreadsheets as a Service Composition Tool

In this paper, we show how spreadsheets, an end-user development paradigm proven to be highly productive and simple to learn and use, can be used for complex service compositions. We identify the requirements for spreadsheet-based service composition, and present our framework that implements these requirements. Our framework enables spreadsheets to send requests and retrieve results from various local and remote services. We show how our tools support different composition patterns, and how the style of declarative dependencies of spreadsheets can facilitate service composition. We also discuss novel issues identified by using the framework in several projects and education.

Analysis and simulation of Web services

Web services––Web-accessible programs and devices––are a key application area for the Semantic Web. With the proliferation of Web services and the evolution towards the Semantic Web comes the opportunity to automate various Web services tasks. Our objective is to enable markup and automated reasoning technology to describe, simulate, compose, test, and verify compositions of Web services. We take as our starting point the DAML-S DAML + OIL ontology for describing the capabilities of Web services. We define the semantics for a relevant subset of DAML-S in terms of a first-order logical language. With the semantics in hand, we encode our service descriptions in a Petri Net formalism and provide decision procedures for Web service simulation, verification and composition. We also provide an analysis of the complexity of these tasks under different restrictions to the DAML-S composite services we can describe. Finally, we present an implementation of our analysis techniques. This implementation takes as input a DAML-S description of a Web service, automatically generates a Petri Net and performs the desired analysis. Such a tool has broad applicability both as a back end to existing manual Web service composition tools, and as a stand-alone tool for Web service developers.

Reliability assurance of application-specific microelectronic circuits : Bing J. Sheu, Wen-Jay Hsu and Vance Tyree. Proc. A. Reliab. Maintainab. Symp., 381 (1990)

HTML5 can be used to develop client applications by composing REST web services within the context of Web 2.0. However, the possibility of implementing cross-platform smartphone applications with REST services needs to be studied. Accordingly, we developed a REST-based cross-platform application with PhoneGap. The application was deployed on the Android, Windows Phone, and iOS platforms; subsequently we evaluated its usability. We observed that REST-based cross-platform smartphone applications can be implemented with HTML5 and PhoneGap, which can be scaled-up into a REST service composition tool. Moreover, the application’s usability remains unaffected on the native platforms and adaptation required only minimal effort.