A Reliable Composite Service Computation Framework

In cloud computing, there exist several classes of web services, and each class of web service contains multiple services which have different Quality of Service (QoS) values. To provide QoS for users, determining the best service composition that meet user's preferences is necessity. Finding the best service composition needs a certain method in order to provide the best combination of QoS with minimum response time, while in some cases, the process is bounded by budget constraint provided in user's preferences. In a simple method, for selecting the best service composition, we need to evaluate nm combinations of n classes of service and m services member. This condition leads to a large computing costs and memory consumption that occur during the process of generating the combination of data. To reduce the number of combinations, we propose an approach for finding the best service composition of web services using skyline algorithm which can adapt different user preferences of QoS. While selecting the best composition, we also take consideration in budget as constraint by selecting the closest user's budget with the best skyline result of services. SalSa skyline algorithm have given the new alternative ways to finding the best candidates of services in each class of service in reasonable time. These happened because we only need to evaluate the smaller parts of members in each class which will need much time if the number of services is plenty. Moreover, we also presented a method to find the best composition of services which able to present the composition that meet the user's budget.

During the early 1990s, workflow technologies were the only ones to offer a transversal integration capacity to the enterprise applications, thus allowing the representation and the enactment of business processes. However, the formalisms developed for workflow specifications were almost systematically activity oriented. Consequently, the resulting process definitions have the advantage to be easily transformable in executable code, but the disadvantage of being prescriptive and rigid. Recent works underline the needs in term of flexible and adaptive workflows, whose execution can evolve according to situations that cannot always be prescribed. In fact, a flexible representation of business processes is an asset to maintain the fit between business processes and their supporting systems in an evolving environment. This article proposes a conceptual framework for an intention‐driven modeling of flexible workflow applications. The purpose of the underlying modeling formalism is to define an integration/orchestration for islands of business process chunks and their support systems in order to create and to maintain the fit between them. The modeling framework offers the ability to represent in the same business process definition the well‐structured process chunks as well as the ill‐structured orad hocones. Copyright © 2005 John Wiley & Sons, Ltd.

ARC: Anomaly-aware Robust Cloud-integrated IoT service composition based on uncertainty in advertised quality of service values

Defending against fake VIP in scant-transparency information systems with QoS differentiation

There are complicated correlations among atomic Web services in a composite service. Considering the influence of such correlations on the quality of composite service is important to do service selection. Now, existing selection approaches don’t consider this issue. Using the idea of division, a dot pattern based composite service selection approach is presented in this paper. The main idea of this approach is that according to the correlation degree of atomic services, dividing the composite service into a series of composite service dots; then regarding the dot as selecting unit to do service selection based on the quality of corresponding dot patterns. Experimental results show that our selection approach can improve the quality of the selected composite service.

To provide Quality of Service (QoS) and data rate differentiation, we investigate in this paper a 2 dimensional optical code division multiple access (OCDMA) technique. A 2D multi-weight coding scheme with parallel mapping technique is developed. The system enhancement is assessed thanks to the use of Forward Error Correction (FEC) based on Low Density Parity Check (LDPC) codes. In order to have an efficient correction power, we develop an adaptation of the LDPC decoding algorithm to the specific multiple access interference distribution in a multimedia OCDMA network. The proposed network permits a high number of users to communicate with high data rates adapted to a multimedia transmission (voice, data and video) with corresponding QoS (10-3, 10-6, 10-9).

Service-oriented architecture permits the composition of web services provided with different Quality of Service (QoS) levels. In a given composition, finding the set of services that optimises some QoS attributes under its constraints is a problem that needs to be solved. Our aim is to propose an intelligent approach to the selection of a Composite Web Service (CWS) based on QoS. This paper reports the authors’ recent research on addressing the issue. An overview on the previously proposed approaches is presented. These approaches correspond to several improvements of an existing multi-agent one, which is well-cited in the specialised literature. Each framework, implemented on JADE (Java Agent Development) framework, improves another one in terms of CPU time and/or QoS score, to reach a new agent-based and scalable framework. The last framework utilises the agents’ ability of negotiation, interaction and cooperation in order to facilitate the selection of composite web services. By using CBR method, the agents can memorise QoS scores and availability. The improvements are related not only to the CPU time but also to the Composite QoS (CQoS) value, while operating in a dynamic environment and taking into account user preferences.

The service composition makes use of the existing services to produce a new value added service to execute the complex business process. The service discovery finds the suitable services (candidates) for the various tasks of the composition based on the functionality. The service selection in composition assigns the best candidate for each tasks of the pre-structured composition plan based on the non-functional properties. In this paper, we propose the broker based architecture for the QoS and business offer aware Web service compositions. The broker architecture facilitates the registration of a new composite service into three different registries. The broker publishes service information into the service registry and QoS into the QoS registry. The business offers of the composite Web service are published into a separate repository called business offer (BO) registry. The broker employs the mechanism for the optimal assignment of the Web services to the individual tasks of the composition. The assignment is based on the composite service providers’s (CSP) variety of requirements defined on the QoS and business offers. The broker also computes the QoS of resulting composition and provides the useful information for the CSP to publish thier business offers.

Web service composition is a promising solution for building distributed applications on the e-business processes, and with web services providing similar functional characteristics, Quality of Service (QoS) is the main factor to differentiate them. It is imperative to provide service consumers with facilities for selecting the only web services for their requirement according to their non-functional characteristics or QoS. However, the selection process is too greatly complicated to meet the requirement of business process. In this paper, the key business process performance model (KBPP) is proposed, and further, the issue of QoS driven service selection for dynamic web service composition is investigated. From the point of view of requirement of KBPP, an evaluation framework with KBPP is proposed, and a new approach to optimize the service selecting based on KBPP is presented. Experimental results show that the proposed approach greatly improves the service selection process in a dynamic and uncertain environment of web services. Simulative experiments are conducted to show the validity and efficiency of the methods.

The software is created and constructed to address particular issues in the applied field. In this context, there is a need to be aware of the crucial characteristics to assess the quality of software. But not all software requires checking all the quality-of-service parameters, resulting in effort loss and time consumption. Therefore, it is required to develop software quality characteristics recommendation model to address and resolve the issue. The proposed work involved in this paper can be subdivided into three main parts (1) a review of popular software quality models and their comparison to create a complete set of predictable, and (2) the design of an ML-based recommendation model for recommending the software quality model and software quality characteristics (3) performance analysis. The proposed recommendation system utilizes the different software quality of service attributes as well as the software attributes where these models are suitably applied to satisfy the demands. Profiling of applications and their essential requirements have been performed Based on the different quality of service parameters and the requirements of applications. These profiles are learned by machine learning algorithms for distinguishing the application-based requirement and recommending the essential attributes. The implementation of the proposed technique has been done using Python technology. The simulation aims to demonstrate how to minimize the cost of software testing and improve time and accuracy by utilizing the appropriate quality matrix. Finally, a conclusion has been drawn and the future extension of the proposed model has been reported.

Nowadays, the problem in business process management (BPM) is that BPM systems should both be easy to use for business process developers and be based on a sound formal method. Business process management systems are often based on semiformal modeling techniques such as event-driven process chains (EPC) or UML. Unlike semiformal modeling techniques, the process calculus CSP comes with mature verification sup- port. Surprisingly little work has been done on using CSP for business process modeling and management. In this paper, we present our approach to business process management, which is based on the observation that CSP is well suited not only for specifying business processes and verifying work???ows but also for executing work???ows using our CSP4J framework. We report on a work???ow server, which is specified in CSP and implemented using our CSP4J framework. The server accepts work???ows that are modeled in CSP and also implemented using CSP4J. This allows us to integrate the mature verification support of CSP into both the management system itself and the development process of the end users’ business process definitions.

Service composition in the Inter-Cloud raises new challenges that are caused by the different Quality of Service (QoS) requirements of the users, which are served by different geo-distributed Cloud providers. This paper aims to explore how to select and compose such services while considering how to reach high efficiency on cost and response time, low network latency, and high reliability across multiple Cloud providers. A new hybrid multi-objective evolutionary algorithm to perform the above task called LS-NSGA-II-DE is proposed, in which the differential evolution (DE) algorithm uses the adaptive mutation operator and crossover operator to replace the those of the Non-dominated Sorting Genetic Algorithm-II (NSGA-II) to get the better convergence and diversity. At the same time, a Local Search (LS) method is performed for the Non-dominated solution set F{1} in each generation to improve the distribution of the F{1}. The simulation results show that our proposed algorithm performs well in terms of the solution distribution and convergence, and in addition, the optimality ability and scalability are better compared with those of the other algorithms.

The development, registration, discovery, and invocation of quality Web services are vital for the successful implementation of applications using Web services. Considerable research focuses on quality for Web services. Unfortunately, current research on Quality of Service (QoS) for Web services is concentrated on service users and the implementation stage. This research highlights the importance of incorporating QoS at the design and development stages; the authors propose the introduction of QoS at the same time as functional requirements. However, Web Service Description Language (WSDL) describes the functional elements of a Web service, and QoS is significant for this description. Therefore, the authors propose an extension to the WSDL through a generic QoS metamodel, incorporating QoS specifications into the functionalities. This paper begins by defining the required QoS specifications for the development of quality Web services and explores the potential of the Unified Modeling Language as a technique and notation to specify QoS. To properly integrate QoS in the design, the authors propose extensions to the existing UML QoS profile. The paper concludes with the evaluation of the proposed framework and summarises its advantages.

With the increasing number of Web services, the Semantic Web research community is moving toward enhancing procedures so that clients may effectively discover appropriate Web services that maximally satisfy not only functional but also non-functional requirements. Using purely syntactic approaches to discover Web services has limited efficiency. Therefore, semantic matchmaking registries can play an important role in providing better results. However, most of the semantic registries make decisions based on only functional requirements. Due to the proliferation of Web services that have similar functionality, there is a need to further filter Web services according to Quality of Service (QoS) specifications. This work introduces a rich QoS ontology inspired from the World Wide Web Consortium that defines relationships among QoS attributes. The QoS attributes defined here are mainly used to define network related characteristics. However, the work can be extended by defining QoS ontologies for other domains. Additionally, we extend the test collection OWLS-TC according to the QoS ontology. The extension is intended to integrate quantified values for QoS attributes into Web service descriptions. A matchmaking algorithm based on similarity measurements is presented. Moreover, deterministic and adaptive parameter control techniques are introduced to guide the requester, when needed, to adjust QoS specifications so better similarity can be achieved. Parameter control algorithms integrate Pellet, an OWL reasoner, to reason about dependencies among QoS concepts in the QoS ontology.

We describe a framework for providing quality-of-service (QoS) guarantees within the endsystem for networked multimedia applications. There are four components in this framework namely—QoS specification, QoS mapping, QoS enforcement, and protocol implementation. QoS specifications are at a high level, and use a small number of parameters to allow applications greater ease in specifying their requirements. Based on the QoS specifications, QoS mapping operations derive resource requirements for each end-to-end session of the application. Important resources considered are the cpu and the network connection. The third component of the framework is QoS enforcement. Enforcement is mainly concerned with providing real-time processing guarantees for protocol code during data transfer. We have implemented a real-time upcall (rtu) facility which is an enhancement to the well known upcall mechanism for structuring protocols, rtus are scheduled using a policy called rate monotonie with delayed pre-emption (rmdp) that takes advantage of the iterative nature of protocol processing to reduce context switching overhead and increase scheduling efficiency. The last component of our framework is an application level protocol implementation model. Protocol code is structured as rtus with attributes that are derived from high level specifications by the QoS mapping operations. We describe techniques to reduce the cost of data movement and context switching in such implementations. The rtu mechanism currently runs in the Netbsd os on Sparc and Pentium based platforms. Initial measurements show that it is an effective means to implement protocols with QoS support.