Bruno Tardiole Kuehne

PEESOS: A Web Tool for Planning and Execution of Experiments in Service Oriented Systems

Performing functionality testing in service-oriented architectures is not a trivial task. The difficulty is especially the large number of components that may be present in a SOA such as brokers, providers, service registries, clients, monitoring tools, data storage tools, etc. Thus, in order to facilitate the process of conducting functional testing and capacity planning in service-oriented systems, we present PEESOS. This first version is a functional prototype that offers facilities to assist researchers and industry to test their new applications, allowing collaborations that can be done between the participants to achieve an appropriate objective when developing a new application. The first results show that it is possible to make a planning environment easier to operate and to readily obtain results for performance evaluation of a target architecture. Since this is a first version of the prototype, it has interface and scalability limitations as well as needing improvements in performance of the logs repository and also in a core engine. We hope that such limitations can be corrected in the near future, including gathering information from the scientific community to make the prototype a useful and accessible tool. PEESOS is on-line and available at http://peesos.wsarch.lasdpc.icmc.usp.br.

A Performance Evaluation for a QoS-Aware Service Oriented Architecture

Web services have emerged as a technology that aims at improving the communication between applications, through the service-oriented paradigm. Researches involving web semantics, ontology and composition of services has currently been developed. However, research in performance evaluating of web services architecture with quality of service support (QoS) is little widespread. Some works separately approach techniques as composition of Web services and models of architectures to improve the quality of Web services. Considering the lack of work involving jointly these different boarding, the purpose of this work is show a performance evaluating of a prototype architecture named WSARCH (Web Services Architecture) that relating quality of service attributes. The initial prototype of the architecture already allows investigate new ways of evaluating performance of Web services based on a contract model and improved existing service discovery solution though the incorporation of quality-of-service issues and related metrics for ranking matches.

Performance evaluation of an automatic web service composition architecture

Automatic Web service Composition (AWSC) is still a big challenge in service oriented architecture (SOA), since there is no platform where is possible to implement and test algorithms for AWSC. This paper presents the Automatic Web service composition Architecture (AWSCA), an architecture in which is possible to implement and run the algorithms for AWSC in an environment proposed for a fair comparison. To reach this objective is proposed a prototype that is able to deploy and execute Automated Composite Web services. This prototype consists of a tool which receives as input a graph with the description of the composite Web service flow, performs and controls the execution and interaction between the services. This approach makes possible to evaluate the performance and to compare the algorithms for AWSC in order to identify which one is a better choice for certain scenarios.

Design and implementation of fault tolerance techniques to improve QoS in SOA

Fault tolerance techniques can improve the trust of users in service oriented architectures as they can ensure data availability. This paper presents an implementation of a novel fault tolerance mechanism in a SOA architecture which simultaneously provides increased availability and better quality of service. In addition to this mechanism, a service selector using reputation ratings of the architecture components is discussed. The selection is based on information from past transactions of the components of the architecture, which allows to identify the best web services able to meet the requests of customers. The mechanisms are tested and a performance evaluation is presented to validate the results.

AWSCS - A system to evaluate different approaches for the automatic composition and execution of web services flows

This paper proposes a system named AWSCS (Automatic Web Service Composition System) to evaluate different approaches for automatic composition of Web services, based on QoS parameters that are measured at execution time. The AWSCS is a system to implement different approaches for automatic composition of Web services and also to execute the resulting flows from these approaches. Aiming at demonstrating the results of this paper, a scenario was developed, where empirical flows were built to demonstrate the operation of AWSCS, since algorithms for automatic composition are not readily available to test. The results allow us to study the behaviour of running composite Web services, when flows with the same functionality but different problem-solving strategies were compared. Furthermore, we observed that the influence of the load applied on the running system as the type of load submitted to the system is an important factor to define which approach for the Web service composition can achieve the best performance in production.

Dynamic Web Service Composition Middleware: A New Approach for QoS Guarantees

This project presents modeling, prototyping and results of the middleware developed for Web service dynamic selection in Web services composition named DWSC-M (Dynamic Web Service Composition Middleware). DWSC-M’s main focus is to choose what Web services will be part of the composite Web services in runtime. The choose is made considering aspects of QoS - Quality of Service. To evalute this approach two algorithms for Web Services selection has been proposed and implemented: the first one uses Random Selection (RS) and the second one uses Euclidean Distance (ED) for the selection of services and considers for this purpose the QoS atributes requested by a client.

The influence of resource allocation on cloud computing performance

This paper makes experimental evaluations that involve the allocation of virtual machines in a cloud environment. Virtual machine allocation is an open research field in cloud, which can lead to the best performance for clients. However, the allocations are made by estimating the number of resources that need to be allocated to the virtual machines in the host without taking account of the possible workload required for these virtual machines. In carrying out this, we set up a cloud prototype, together with virtual machines with the same configuration as that for Amazon and Microsoft providers, so that our prototype could be validated. After this, we allocated as many virtual machines as possible in a single host based on our own infrastructure and involving homogeneous workloads and heterogeneous workloads. The results showed that the benefits obtained from heterogeneous sets of virtual machines were better than the homogeneous sets.

A Performance Evaluation of an Automatic Web Services Composition System

The automatic composition of Web Services has been explored in the literature from different standpoints. It aims to create an execution plan for the flow of Web Services based on requests made and sent by the client, by following the stages necessary for the generation of composite services and then carrying out the execution of the workflow that has been designed. However, no research studies have been found that undertake the whole process of an automatic composition and execution, from the users request to the execution of the services chosen as a solution. Therefore, the goal of this paper is to evaluate the performance of an automatic Web Service composition, since the request made by the client, to the delivery of the results of the executed composition. This article examines the integration between two tools, the automatic web service composition system and the extensible platform to evaluate semantic web services with the aim of conducting a performance evaluation of an entire process of automatic composition of Web services.

CM Cloud Simulator: A Cost Model Simulator Module for Cloudsim

The vast cloud computing environment holds out good prospects for researchers in the computing technology field. However, with several Cloud providers offering different pricing models, the evaluation and modeling of Cloud environments and applications are getting harder because there is a lack of tools for this task. We propose the CM Cloud Simulator to fill this gap since it provides a comprehensive and dynamic simulation of applications with various deployment configurations and incurs the cost it would require when implemented in a Cloud Provider, according to the cost model of any service provider. The CM Cloud Simulator also provides custom-built cost models through the XML file.