Single Web Service Research Articles

Obtaining P3P privacy policies for composite services.

With the development of web services technology, web services have changed from single to composite services. Privacy protection in composite services is becoming an important issue. P3P (platform for privacy preferences) is a privacy policy language which was designed for single web services. It enables service providers to express how they will deal with the privacy information of service consumers. In order to solve the problem that P3P cannot be applied to composite services directly, we propose a method to obtain P3P privacy policies for composite services. In this method, we present the definitions of Purpose, Recipient, and Retention elements as well as Optional and Required attributes for P3P policies of composite services. We also provide an instantiation to illustrate the feasibility of the method.

Measuring the Qualitative Feature of Combined Services

The combination of web services is the result of complex and increasing needs of the users and disability of single web services in resolving the user’s needs. One of the important challenges in the field of web 2.0 is the combination of web services based on their qualitative features. Since it is probable that there would be several different combinations of services for achieving a specific goal, choosing the service is based on some qualitative features like combining, availability, acceptability, service cost and security. One of the important issues is the quantitative survey of combining rate of the two services shared on the combination so that they have the ability to combine with each other, correctly. In order to measure the combining ability of services, in the first stage, the more number of effective factors on combining features of services are surveyed in comparison with the present methods. In the second stage, metric is introduced for the effective factors, and in the third stage, an appropriate weight for each factor is found and finally, based on their relationships with each other, a more accurate rate of combining is obtained.

Proposal of Mashup Framework for End Users

This paper proposes a new mashup framework for end users and discusses the usability of the proposed framework. Recently, a wide variety of requirements for web services has arisen because more users are using web services in their daily lives. However, a single web service cannot satisfy all requirements due to the variety of those requirements. To satisfy the requirements, it is important to have web service mashups which coordinate a number of web services to match the requirements. A mashup framework is a software environment that makes it easy for developers to make mashups. The challenge of this study is to develop a new mashup framework for end users with a new mashup model and modules. The model and the modules are implemented in the proposed framework.

Analisis Perbandingan Unjuk Kerja Sistem Penyeimbang Beban Web Server dengan HAProxy dan Pound Links

The development of internet technology has many organizations that expanded service website. Initially used single web server that is accessible to everyone through the Internet, but when the number of users that access the web server is very much the traffic load to the web server and the web server anyway. It is necessary for the optimization of web servers to cope with the overload received by the web server when traffic is high. Methodology of this final project research include the study of literature, system design, and testing of the system. Methods from the literature reference books related as well as from several sources the internet. The design of this thesis uses Haproxy and Pound Links as a load balancing web server. The end of this reaserch is testing the network system, where the system will be tested this stage so as to create a web server system that is reliable and safe. The result is a web server system that can be accessed by many user simultaneously rapidly as load balancing Haproxy and Pound Links system which is set up as front-end web server performance so as to create a web server that has performance and high availability.

Implementasi Load Balancing Web Server Menggunakan Metode LVS-NAT

Web server plays a vital role on serving requests from clients. As Internet users grows so fast, the request number increases significantly, thus reducing the overall performance of the web server. One solution is to implement a load balancing system.In this paper, we implement load balancing with Linux Virtual Server to distribute the load to several machines within a cluster. We compared Round Robbin and Least Connection algorithm. The study reveals that load balancing using LVS-NAT can double the throughput output compared to single web server, but less significant on response time and CPU utilization. Implementing LVS-NAT using round robbin algorithm is more robust in optimizing the throughput, CPU utilization, and response time compared to least connection.

Movement-aware and QoS-driven indoor location and mobile service discovery framework

The ever evolving wireless technology and the advances in mobile devices induced a growing interest in indoor location-based services ILBS. In this paper, we propose an ILBS discovery framework that finds the accurate indoor location of mobile users and provides information about services within the users' surrounding area keeping in mind the client's Quality of Service QoS. It also provides support for movement-aware services where the path the mobile user takes is recorded to provide richer awareness of the client's context than pure location. An ontology chain is proposed to support service discovery and to capture context information dynamically from different client's locations, then map it to both single and composite web services. Comprehensive experiments, comparative study with other ILBS approaches, and performance evaluation were conducted. The results demonstrate that our proposed scheme outperforms the state-of-the-art methods presented in the literature and achieves very high localisation and service discovery accuracy.

Process model-based atomic service discovery and composition of composite semantic web services using web ontology language for services (OWL-S)

Web Service composition has become indispensable as a single web service cannot satisfy complex functional requirements. Composition of services has received much interest to support business-to-business (B2B) or enterprise application integration. An important component of the service composition is the discovery of relevant services. In Semantic Web Services (SWS), service discovery is generally achieved by using service profile of Ontology Web Languages for Services (OWL-S). The profile of the service is a derived and concise description but not a functional part of the service. The information contained in the service profile is sufficient for atomic service discovery, but it is not sufficient for the discovery of composite semantic web services (CSWS). The purpose of this article is two-fold: first to prove that the process model is a better choice than the service profile for service discovery. Second, to facilitate the composition of inter-organisational CSWS by proposing a new composition method which uses process ontology. The proposed service composition approach uses an algorithm which performs a fine grained match at the level of atomic process rather than at the level of the entire service in a composite semantic web service. Many works carried out in this area have proposed solutions only for the composition of atomic services and this article proposes a solution for the composition of composite semantic web services.

Trade-Off Analysis on QoS-Aware Dynamic Web Services Composition with Evolutionary Optimization

Nowadays web services are a distributed technology that can successfully solve integration problems between heterogeneous systems. The supporting technology for web services has been widely studied mainly focusing on the standardization of service transactions and running a single and multiple web services. In dealing with complex and large-scale web service requests, there is a foreseeable bottleneck of supporting technology. QoS-Aware web service composition is NP-hard problem and one of the most challenging problems in web services. This paper proposes an optimization solution using enhanced evolutionary algorithm (EA) for the dynamic composition of web service components and performs the trade-off analysis on dynamic composition of multi domain with multi objectives. First, we propose the Distance Function Based Evolutionary Algorithm (DFBEA) techniques to automatically select optimal combinations of web service components from available component repositories. Second, using multi domain with multi objectives case study, we demonstrate the trade-off analysis on efficiency and effectiveness of the proposed technique and algorithm through experimental evaluation of component selection, and furthermore a comparison with other optimization techniques will be proposed.

Web Services Based Information Retrieval Agent System for Cloud Computing

Cloud computing is Internet based system development in which large scalable computing resources are provided “as a service” over the Internet to users and has attracted more and more attention from industry and research community. However, the concept of cloud computing does not provide facilities for the knowledge discovery and information retrieval; i.e. clouds need to be intelligent and autonomous. On the other hand, Web Service plays important role in Service Oriented Computing (SOC) in cloud environment. Retrieving desired specific information from Web Services on cloud environment cannot be done by single Web Service. So, there should be a possibility to combine existing services together in order to fulfil the request. To compose Web Services, Agents can give great help. Therefore, this research mainly focus on providing a framework for retrieving information from Cloud using composite Web Services by means of Multi-Agent System.

Web Services Composition Algorithm Based on Mine Domain Ontology

Through analyzing the commonness of mine domain, the paper proposes a composition algorithm of web services based on mine ontology in order to integrate business of mine industries. The paper specially gives the formal description of mine domain ontologies, and proposes the composition algorithm which uses mine domain ontologies. The practice proves that web services composition in certain domain can enhance the efficiency and qulity of services composition. Web services are rapidly changing the landscape of software engineering on account of their outstanding traits, for example big granularity, loose coupling and late-binding mechanisms.Web services selection is the foundation of services composition,and selection methods can be divided into two classes: functional attributes based web services selection method and QoS based web services selection method.The first method is usually used to match single web service and recent literature[1] discusses global function matching problem.Because WSDL lacks semantic information, some scholars[2][3] add semantic information to WSDL in order to increase services matching quality. The second method usually discusses QoS in the global scope,but the selection efficiency and quality are the considered issue. Recent literatures[1][4] add semantic information to QoS attributes ,and literature[2] considers web services selection using the two methods comprehensively. Web services selection usually does not involve certain domain, but the theory and practice of software engineering prove that software reuse in certain domain is easier to succeed. For web services selection based on functional attributes, services selection in certain doamin(for example mine domain) is easier to add semantic information to WSDL because of domain ontology ,and for services selection based on QoS attributes, we can design more appropriate QoS attribute model according to domain requirements. So researching web services selection in certain domain has theoretical and realistic significance. In fact, some literatures begin to research web services selection and composition in certain domain. Literature[3] proposes an intelligent telecommunication service model based on semantic web services according to design the telecommunication service domain ontology, literature[5] discusses web services detection based on oil and gas domain ontology automaticly, and has a good effect. The paper proposes a composition algorithm of web services based on mine domain ontology and the details is organized as follows. Section I gives the formal description of mine domain ontology; Section II is the composition algorithm which bases on mine domain ontology; Section III concludes this paper.

MicroMAIS: executing and orchestrating Web services on constrained mobile devices

Mobile devices with their more and more powerful resources allow the development of mobile information systems in which services are not only provided by traditional systems but also autonomously executed and controlled in the mobile devices themselves. Services distributed on autonomous mobile devices allow both the development of cooperative applications without a back-end infrastructure and the development of applications blending distributed and centralized services. In this paper, we propose MicroMAIS: an integrated platform for supporting the execution of Web service-based applications natively on a mobile device. The MicroMAIS platform is composed of mAS and μ-BPEL. The former allows the execution of a single Web service, whereas the latter permits the orchestration of several Web services according to the WS-BPEL standard. Copyright © 2011 John Wiley & Sons, Ltd.

Scalable and efficient web services composition based on a relational database

Abstract Recently, there has been growing interest in web services composition. Web services composition gives us a possibility to fulfil the user request when no single web service can satisfy the functionality required by the user. In this paper, we propose a new system called PSR for the scalable and efficient web services composition search using a relational database. In contrast to previous work, the PSR system pre-computes web services composition using joins and indices and also supports semantic matching of web services composition. We demonstrate that our pre-computing web services composition approach in RDBMS yields lower execution time for processing user queries despite of and shows good scalability when handling a large number of web services and user queries.

A Method for Web Services Fault Tolerance Based on Ripple Effect Analysis

In this paper we first establish a dependency matrix over the inputs of web services in composition and the degree of dependency between the interface parameters for a single web service. Operating over the matrices, the ripple effect of a single service's fault at runtime has been analysed and computed. Based on this, we have looked for a method to substitute the failing service with an equivalent one at runtime. Using simulations and real examples we have confirmed the effectiveness of the method shown in this paper.

Web Service with Parallel Processing Capabilities for the Retrieval of CAD Assembly Data

Since CAD data is used as master data throughout the lifecycle of a product, it is important to provide a means for efficiently sharing CAD data among systems used for collaborative product development. Web Services, a type of distributed object technology, is adequate for this purpose; in a previous study [7], the authors proposed the architecture of Web Services for CAD (WSC) for the retrieval of CAD data. CAD data are classified into CAD assembly and part data. Since product design is typically modeled in the form of CAD assembly data, it is worth to consider this application when implementing a service for CAD data retrieval. In this study, the authors first propose a concept of parallel Web Service, which is an extension of WSC and whose goal is the rapid retrieval of CAD assembly data. They then discuss the technical details that can lead to its realization. Finally, experimental results regarding the performance of assembly data retrieval by the parallel Web Service are presented and compared with analogous performance by a single Web Service.

Stochastic bounds for composite Web services response times

In this paper, we propose bounding models, which provide upper and lower bounds on response time in composite Web service model, for alleviating the state explosion problem. The considered models have heterogeneous servers and the number of elementary Web services can be very large. More precisely, we study two types of composite Web services. First, we investigate the performance of a single composite Web service execution instance. Second, this assumption is relaxed (i.e. multiple composite Web services execution instances are considered). These models allows to find trade-off between the accuracy of the bounds and the computation complexity.

Employing collective intelligence for user driven service creation

With advances in computing technologies and active user participation through smart devices such as the iPhone and Android, user needs are becoming varied and complex. It is quite natural, then, that a single Web service may not be sufficient to fully satisfy the diverse goals of users in their daily lives. A set of cohesively connected Web services/mashups may be able to deal with these goals. An increasing number of open APIs can facilitate various types of service compositions with users as the service creators. Recently, Internet, telecommunications, and third-party providers have opened their services to the public in the form of open APIs, a trend following the Web 2.0 paradigm. However, most service creation environments do not have sufficient knowledge (particularly, available services and their functionality) to support service creation by users. The problem of knowledge scarcity is that users may have difficulty in finding relevant open APIs for a given situation, finally resulting in rather straightforward types of service. In this article we present two kinds of collective intelligence for user-driven service creation: the user's own experiences in service composition, and activity knowledge from the web. These collective intelligence types will aid in creating enduser service compositions by enforcing knowledge support in terms of user experiences and activity-aware functional semantics, and will finally accelerate the development of various kinds of converged applications. Using the beneficial roles of collective intelligence as key enablers of future service creation environments, this article also shows a new potential for user-driven composite services within the next few years.

A service process optimization method based on model refinement

Due to the limited functionality of a single Web service, a group of Web services often need to be linked together, working as an integrated service process, to provide value-added functions. One of the key issues in modeling such an integrated service process, in addition to the functions it can provide, is the assurance of service quality. As Web services have become increasingly popular, a number of Web services with similar functions but different qualities can be readily found on the Internet. Which services you select to combine into an integrated service process severely impacts the quality of that service process. The quality of a service process is also subject to its structure. In the paper, a refinement method for quality optimization of a service process model is proposed. The refinement method takes into account the selection of Web services and the structure of the service process simultaneously. More specifically, in this method, a service process model is transformed into a process structure tree for quality calculation and then a genetic algorithm is applied to refine the service process model for quality optimization. The method, together with the experiment results, is discussed in detail in the paper. The experiment results show this method can optimize the quality of the service process by applying refinement method according to the requirements.

Research on Marketing Cooperation System Based on Multi-Agent Services Aggregation Driven by Requirement

The web service has great significance and value since it represents a large industrial sector and huge trade interests, but the function of a single web service is too small to satisfy the need of service requestor, so it is necessary to combine a mount of simple services to satisfy the complex and dynamic requirement in practice, then the problem of web services composition is one of the research hotspot. This paper generalized the primary interaction processes between enterprise and customer in marketing, encapsulated the special function for marketing works as the agent, and considered the marketing as the cooperation process of agents focusing on requirements, and based on that a multi-agent based marketing cooperation system (MAMCS) is established and the agent ontology is designed according to JADE, finally the negotiation mechanism is built. The method of multi-agent services aggregation driven by requirement supposed in this paper can improve the utilizing effect of service, reduce the difficulty of services composition, and realize the automatic purpose of services composition. Moreover, by combining the merits of agent technique the initiation and intelligence of the services are improved, that safeguard the best interests of the service providers due to they have an option on requirements. Index Terms—Marketing; Multi-Agent; Web Service; Aggregation; System

Coordinated session-based admission control with statistical learning for multi-tier internet applications

Popular Internet applications deploy a multi-tier architecture, with each tier provisioning a certain functionality to its preceding tier. In this paper, we address a challenging issue, session-based admission control for peak load management for multi-tier Internet applications. The session-based admission control approach (SBAC) designed for a single Web server is not effective for a multi-tier architecture. This is due to the fact that the bottleneck in a multi-tier website dynamically shifts among tiers as client access patterns change. Admission control based on only the bottleneck tier is not efficient as different sessions impose different resource consumptions at the different tiers. First, we propose a multi-tier measurement based admission control (MBAC), which pro-actively accepts different session mixes based on the utilization state of all tiers. More importantly, we design a coordinated session-based admission control approach (CoSAC) based on a machine learning technique. It uses a Bayesian network to correlate the states of all tiers. The probability with which a session is admitted is determined by the probabilistic inference of the network after applying the evidence in terms of utilization and processing time at each tier to the network. We compare CoSAC with MBAC and a Blackbox approach tailored from SBAC, using the industry standard TPC-W benchmark in a typical three-tier e-commerce website. Experimental results demonstrate the superior performance of CoSAC with respect to the effective session throughput.

Fair non-repudiation for web services transactions

To safeguard the interests of transacting parties, non-repudiation mechanisms need to assure fairness and timeliness. The non-repudiation service currently implemented usually does not consider the requirement of fairness and the fair non-repudiation protocols to date can not be suitably applied in real environment due to its complex interaction. This paper discusses the transaction-oriented non-repudiation requirement for Web services transaction, analyzes the constraints of the traditional model for the available fair non-repudiation protocols and designs a new Online-TTP fair non-repudiation protocol. The new protocol provides a fair non-repudiation solution to secure Web services transactions and can be embedded into a single Web service call. The protocol adopts evidence chained to decreasing the overhead of evidence verification and management and alleviates the overhead of certificate revocation checking and time-stamp generation for signatures. The protocol has strong fairness, timeliness, efficiency and practicability.