The numerous heterogeneities among different providers make platform as a service interoperability an interesting and complex research and practical problem. For example, each provider offers its own remote application programming interfaces (APIs). The main aim of this paper is to identify and address service-level interoperability issues when using APIs from different commercial providers of platform as a service. First, we define use case to add current user information from one platform as a service offer to the application hosted on another offer. To address interoperability problems, the ontology driven data mediation will be used and tested in this use case. Remote vendors' APIs are implemented as web services. Resulting web operations and their inputs/outputs are semantically annotated using cross-PaaS concepts from the developed platform as a service OWL ontology. Next, SAWSDL and XSLT are used to define service type mappings. Actual composition of platform as a service APIs is implemented by means of AI planner and developed Java web application. Testing and validation was performed on a case where current Sales force's user is added to data container in Vosao content management system deployed on Google App Engine. Novelty of the paper is a specific application domain (composition of operations defined in PaaS APIs) and new algorithm for identification of interoperability problems.

The increasing presence and adoption of Web services on the Web has promoted the significance of management of new service development for service developing sectors. The major challenge is that how to find missing but potentially valuable Web services to be developed. This problem can be divided into two sub-problems: finding missing Web services and measuring the added-value of the introduced services. This paper addresses a plausible solution to the first sub problem. Given a collection of Web services, we propose a framework for suggesting a set of candidate Web services that can be introduced to the collection. These suggested services are novel and do not present in the given collection. Our solution relies on the network structure of Web services for finding and recommending new Web services and utilizes the already observed properties of Web services networks for collective evaluation of the suggested services. The proposed solution is evaluated using 753 semantically annotated Web services. The experimental results shows that the proposed framework provides web service community with new network driven methods for finding and evaluation of new Web services.

In the past years various methods have been developed which require semantic annotations of Web services as an input. Such methods typically leverage discovery, match-making, composition and execution of Web services in dynamic settings. At the same

Information diffusion has been studied between and within biosphere, microblogs, social networks, citation networks and other domains, where the network structure is present. These studies have turned to be useful for acquiring intrinsic knowledge for strategic decision making in related areas, for example, planning online campaigns in case of microblogs and blogosphere. In the context of data-centric Web services, information exchange patterns will reveal practical heuristics for efficient Web services selection and composition. For example, by possible knowledge that there is information flow between Web services of \textit{Financial Analysis Services} and \textit{Enterprise Resource Planning Services}, as outlined by our experimental results, the potential applications, which interact with \textit{Financial Analysis} services, can be adjusted to take advantage of \textit{Enterprise Resource Planning} services as well. In this paper we present a method for analyzing information diffusion between categories of data-centric Web services. The method operates on a Web services network constructed by linking interface descriptions of categorized Web services. The proposed method is evaluated on a case study of global Web services. The results indicate high potential of the proposed model in understanding interactions between categories of Web services.

In recent years many methods have been proposed, which require semantic annotations of Web services as an input. Such methods include discovery, match-making, composition and execution of Web services in dynamic settings, just to mention few. At the same time automated Web service annotation approaches have been proposed for supporting application of former methods in settings where it is not feasible to provide the annotations manually. However, lack of effective automated evaluation frameworks has seriously limited proper evaluation of the constructed annotations in practical settings where the overall annotation quality of millions of Web services needs to be evaluated. This paper describes an evaluation framework for measuring the quality of semantic annotations of large number of Web services descriptions provided in form of WSDL and XSD documents. The evaluation framework is based on analyzing network properties, namely scale-free and small-world properties, of Web service networks, which in turn have been constructed from semantic annotations of Web services. The evaluation approach is demonstrated through evaluation of a semi-automated annotation approach, which was applied to a set of publicly available WSDL documents describing altogether ca 200 000 Web service operations.

The advent of mobile computing devices and development of wireless and ad-hoc networking technologies has led to growth of infrastructure-less environments. Mostly, these environments lie at the edges of Internet i.e. they are disconnected/sparsely connected to rest of the world. In order to exploit the access to such edges of Internet, we propose and experimentally evaluate an interoperability middleware that synergizes P2P technology, message queuing support and a passive distributed UDDI for Web services discovery and invocation.

This paper addresses the problem of identifying redundant data in large-scale service-oriented information systems. Specifically, the paper puts forward an automated method to pinpoint potentially redundant data attributes from a given collection of semantically-annotated Web service interfaces. The key idea is to construct a service network to represent all input and output dependencies between data attributes and operations captured in the service interfaces, and to apply centrality measures from network theory in order to quantify the degree to which an attribute belongs to a given subsystem. The proposed method was tested on a federated governmental information system consisting of 58 independently-maintained information systems providing altogether about 1000 service operations described in WSDL. The accuracy of the method is evaluated in terms of precision and recall.

In this paper we demonstrate how the Web services based solutions can be effectively utilized and integrated into robotic world. In particular, we consider robotic systems where overall control is not embedded into any of the robots and the local behavior of each robot is loosely dependent on behavior of other robots. We propose an architecture for swarm action planning based on Web services paradigm exploiting a problem ontology for service discovery, linear logic based service composition for action planning and a task allocation layer for finding the most suitable robot to perform an action. In our solution all entities in the system expose their functionalities as Web services and allow dynamic service discovery and selection.

Experiments with large service models of a federated governmental information system are described. Large syntactic Web service models are being used for automatic composition of services in an e-government information system. A visual tool developed in software environment CoCoViLa has been used for handling syntactic service models and synthesis of compound services. For a given specification and a goal, the tool synthesizes a program that generates a service description in OWLS and BPEL.

The deregulation of the electricity industry in many countries has created a number of marketplaces in which producers and consumers can operate in order to more effectively manage and meet their energy needs. To this end, this paper develops a new m

This paper introduces a method for automatic composition of semantic Web services using Linear Logic (LL) theorem proving. The method uses semantic Web service language (DAML-S) for external presentation of Web services, while, internally, the services are presented by extralogical axioms and proofs in LL. We use a process calculus to present the composite service formally. The process calculus is attached to the LL inference rules in the style of type theory. Thus the process model for a composite service can be generated directly from the proof. The subtyping rules that are used for semantic reasoning are presented with LL inference figures. We propose a system architecture where the DAML-S translator, the LL theorem prover and the semantic reasoner can operate together to fulfill the task. This architecture has been implemented in Java.

Abstract. This paper describes how the cash-point service can be modelled and simulated using the NUT system.