Web Service-based Systems Research Articles

DCServCG: A data-centric service code generation using deep learning

Modern software development paradigms, including Service-Oriented Architecture (SOA), tend to make use of available services e.g., web service Application Programming Interfaces (APIs) to generate new software. Thus, for the further advancement of SOA, the development of accurate automatic tasks, such as service discovery and composition, is necessary. Most of these automated tasks rely heavily on web service metadata annotation. The lack of machine-readable documentation and structured metadata reduces the accuracy and volume of automatic data annotation, negatively affecting the performance of automated SOA tasks. This study aims to propose automatic code completion for improving web service-based systems by identifying and capturing service usage collected from public repositories that share Open Source Software (OSS). To this end, a Data-Centric Service Code Generation (DCServCG) model is proposed to improve old-fashioned, general-purpose code generators that neglect essential service-based code characteristics e.g., sequence overlap and bias issues. DCServCG takes advantage of the data-centric concept, i.e., conditional text generation, to overcome the mentioned issues. We have evaluated the approach from the point of view of language modeling metrics. The obtained results indicate that the usage of the data-centric approach reduces perplexity by 1.125. Moreover, the DCServCG model uses de-noising and conditional text generation, which is trained on the transformer by distilling the knowledge, DistilGPT2 (82M parameters) trained faster and its perplexity is 0.363 lower than ServCG (124M parameters) without de-noising and conditional text generation, which lower perplexity value indicates better model generalization performance.

Self-Healing in Web Service-Based Systems Using QoS

Availability of components in online systems cannot be guaranteed due to the unstable nature of the web (updates, changes, etc.). A well-designed system must take this fact into account in order to ensure the availability of services which is a very difficult challenge due to the confidentiality and autonomy of each service component. An interesting solution for this is to tolerate these problems at the composite level by having a mechanism of recovery, called Self-healing. In this work, we proposed a solution that consists of implementing a formal approach, making it possible to model a business process (web service composition) by timed automata of the type daTA, while ensuring the quality of service taking into account the functional and non-functional needs of the system (in this case, the QoS represents the response time). The main objective of this project is to create a system that allows you to compare two web service compositions in pairs, to decide whether they are equivalent or not to ensure a perfect self-healing working system by the end.

Presenting a new fuzzy system for web service selection aimed at dynamic software rejuvenation

As an effective technique to counteract software aging, software rejuvenation is applied in continuously running applications such as web service-based systems. In such systems, web services are allocated depending on the requirements of receivers and the facilities of servers. One of the challenging issues during assignment of web services is how to select the appropriate server to minimize faults. In this paper, we proposed dynamic software rejuvenation in the form of a proactive fault-tolerance technique based on fuzzy system. While including a threshold for the rejuvenation of each web service, we carried out the training phase based on the features of the service providers as well as the receivers’ requirements. The results of simulations revealed that our strategy can mitigate the failure rate of web services by 45, 40, 23, and 12% in comparison with the non-fuzzy, regression-based, Markov-based, and ACOGELS-based web service rejuvenation strategies, respectively.

Dynamic software rejuvenation in web services: a whale optimizationalgorithm-based approach

In this paper, we suggest a method for determining the restarting time for web services to increase availability, known as rejuvenation. We consider different parameters such as number of users, maximum service request number, response time, and throughput of a web service to determine its restarting time. Software rejuvenation is an effective technique to counteract software aging in continuously running applications such as web service-based systems. In these systems, web services are allocated based on the needs of the receivers and facilities of servers. One of the challenges while assigning web services is selecting the appropriate server to reduce faults. Since the selection of a server among candidates while maintaining the optimal quality of service is an NP-hard problem, metaheuristics seem to be suitable. In this paper, we propose dynamic software rejuvenation as a proactive fault-tolerance technique based on the whale optimization algorithm. The threshold for the rejuvenation of each of the web services is considered and training is done based on the features of the service providers as well as the needs of the receivers. The whale optimization algorithm with the criterion of movement radius is utilized for flexibility of web service provider selection. Here, we detect and rejuvenate systems that required rejuvenation before the occurrence of a fault. The simulation results reveal that our strategy can decrease the failure rate by an average of 30 percent in comparison with state-of-the-art strategies and improve the system availability in web services.

Automatic service abstraction through data, information and knowledge prioritisation

Web service is a popular solution to integrate components when building a software system, or to allow communication between a system and third-party users, providing a flexible and reusable mechanism to access its functionalities. Scientists have been proposing numerous models for defining anything 'as a service (aaS)', including discussions of products, processes, data and information management, and security as a service. Various web service-based systems are prevailing in health service, personalised recommendation provision. We propose a framework towards constructing and searching typed resources in terms of data, information and knowledge through a hierarchy composing data graph, information graph and knowledge graph in order to improve performance in accessing and processing resources. We use cases to illustrate the mechanism of the framework.

Formal Specification of Adaptable Semantic Web Services Composition

This article proposes a formal specification method for Web services composition based on context-aware semantic planning graph technique. The authors first use a graph planning technique to conceive an adaptable semantic Web services composition. They use an ontology based context model for extending Web services descriptions with information about the most suitable context for its use. Then, the composition problem is transformed into a semantic context aware graph planning problem to build a set of best-composed Web services based on the user's context. Because of the error-prone nature of the Web services composition process, and with the integration of context information in this process, the complexity of Web services-based systems is increasing, hence the need for formal specification and verification approaches of such systems. The authors seek to use CCA calculus, to formalize Web services composition expressed in terms of adaptable OWL-S, and transform the description of workflow patterns into the description patterns in terms of CCA, a calculus for context-aware ambients.

Architectural method to design and control dynamic composite web services

Nowadays, Web services constitute the core technology of IT infrastructure that has emerged in response to a fundamental shift in the way enterprises conduct their business. A componentised model emerges as the natural architecture for Web services-based applications. Using Mop-ECATNets formalism (Meta-Open Extended Concurrent Algebraic Term Nets) a sort of high-level Petri nets we show, in this paper, how we can ensure the formal specification of the dynamic Web services and control their interactions as well as their dynamic composition. Furthermore, in order to formally verify and execute Web services-based systems specifications, we implement Mop-ECATNet model in Maude system using an MDA (Model-Driven Architecture)-based approach.

Empirical rules-based view abstraction for distributed model driven development

Empirical rules are among the most widely employed approaches for processing view abstraction for UML, which can support model simplification, consistency checking, and complexity reduction. However, empirical rules face challenges such as completeness validation, consistency among rules, and composition priority arrangement. The challenge of composition is enlarged in the environment of distributed model-driven development for web service-based systems, where redundant information/data is emphasised. The same redundant information can be expressed in different forms that comprise different topological structures representing the same part of the system. Such variation will result in choosing different compositions of rules executed in different orders, which will increase the severity of the current non-determinism from the empirical probability of some rules. We investigate the effect of redundancy on rule application through designing a simulated distributed storage for an example model. We construct finite-state automaton to unify empirical rules while relieving the side effects caused by redundancy.

Empirical rules-based view abstraction for distributed model driven development

Empirical rules are among the most widely employed approaches for processing view abstraction for UML, which can support model simplification, consistency checking, and complexity reduction. However, empirical rules face challenges such as completeness validation, consistency among rules, and composition priority arrangement. The challenge of composition is enlarged in the environment of distributed model-driven development for web service-based systems, where redundant information/data is emphasised. The same redundant information can be expressed in different forms that comprise different topological structures representing the same part of the system. Such variation will result in choosing different compositions of rules executed in different orders, which will increase the severity of the current non-determinism from the empirical probability of some rules. We investigate the effect of redundancy on rule application through designing a simulated distributed storage for an example model. We construct finite-state automaton to unify empirical rules while relieving the side effects caused by redundancy.

Transition of legacy systems to semantically enabled applications: TAO method and tools

Despite expectations being high, the industrial take-up of Semantic Web technologies in developing services and applications has been slower than expected. One of the main reasons is that many legacy systems have been developed without considering the potential of the Web in integrating services and sharing resources. Without a systematic methodology and proper tool support, the migration from legacy systems to Semantic Web Service-based systems can be a tedious and expensive process, which carries a significant risk of failure. There is an urgent need to provide strategies, allowing the migration of legacy systems to Semantic Web Services platforms, and also tools to support such strategies. In this paper we propose a methodology and its tool support for transitioning these applications to Semantic Web Services, which allow users to migrate their applications to Semantic Web Services platforms automatically or semi-automatically. The transition of the GATE system is used as a case study.

Modeling and managing the variability of Web service-based systems

Web service-based systems are built orchestrating loosely coupled, standardized, and internetworked programs. If on the one hand, Web services address the interoperability issues of modern information systems, on the other hand, they enable the development of software systems on the basis of reuse, greatly limiting the necessity for reimplementation. Techniques and methodologies to gain the maximum from this emerging computing paradigm are in great need. In particular, a way to explicitly model and manage variability would greatly facilitate the creation and customization of Web service-based systems. By variability we mean the ability of a software system to be extended, changed, customized or configured for use in a specific context. We present a framework and related tool suite for modeling and managing the variability of Web service-based systems for design and run-time, respectively. It is an extension of the COVAMOF framework for the variability management of software product families, which was developed at the University of Groningen. Among the novelties and advantages of the approach are the full modeling of variability via UML diagrams, the run-time support, and the low involvement of the user. All of which leads to a great deal of automation in the management of all kinds of variability.

The practical application of a process for eliciting and designing security in web service systems

Best practices currently state that the security requirements and security architectures of distributed software-intensive systems should be based on security risk assessments, which have been designed from security patterns, are implemented in security standards and are tool-supported throughout their development life-cycle. Web service-based information systems uphold inter-enterprise relations through the Internet, and this technology has been revealed as the reference solution with which to implement Service-Oriented Architectures. In this paper, we present the application of the Process for Web Service Security (PWSSec), developed by the authors, to a real web service-based case study. The manner in which security in inter-organizational information systems can be analyzed, designed and implemented by applying PWSSec, which combines a risk analysis and management, along with a security architecture and a standard-based approach, is also shown. We additionally present a tool built to provide support to the PWSSec process.

Taming Web Services from the Wild

Service-oriented computing is about building new cross-organizational applications by combining, composing, consuming, or interconnecting existing services. So, why do most composite Web service-based systems currently rely on pre-established relationships that aren't created by automated, dynamic discovery and integration? One perceived reason is the inconsistency in service-based interface descriptions and message names. Here, the authors investigate whether human nature - specifically, software developers' tendencies to name service descriptions in significantly consistent ways - can provide syntactical methods for service discovery..

VxBPEL: Supporting variability for Web services in BPEL

Web services provide a way to facilitate the business integration over the Internet. Flexibility is an important and desirable property of Web service-based systems due to dynamic business environments. The flexibility can be provided or addressed by incorporating variability into a system. In this study, we investigate how variability can be incorporated into service-based systems. We propose a language, VxBPEL, which is an adaptation of an existing language, BPEL, and able to capture variability in these systems. We develop a prototype to interpret this language. Finally, we illustrate our method by using it to handle variability of an example.

Verifying the Reliability of Web Services Interactions for the Robot Communication Platform

As Loosely Coupled Robot Communication and the common robot service platform using Web Services gain acceptance, the multi-vendor/multi-implementation environment is becoming increasingly disseminated and interoperability increasingly critical. In contrast Reliable messaging is a key to such Web Services-based systems, but no openly available verification suite currently exists for this technology. We discuss requirements of conformance and interoperability tests for Web Services reliability, and report results of coverage tests and application-driven tests using the verification suite we developed for reliable messaging. This suite verified implementations conforming to WS-Reliability, a reliable message specification. It also proves that application-driven tests requiring neither test program installation nor probe, effectively ensure interoperability in actual application together with common robot service platform implementation.

Migrating Legacy Information Systems to Web Services Architecture

Web services-based systems with Service-Oriented Architecture (SOA) are widely accepted as one of the possible solutions for an enterprise information system to retain/keep its old legacy systems. Using this aforementioned architecture, enterprise information systems tend to be more flexible and agile to fit into the capricious business environment, and thus, will be easier to be integrated with other additional applications. The purpose of this manuscript is to propose a migrating solution to convert the architecture of the legacy system into SOA with a systematic approach. This proposed methodology is different from other traditional object-oriented approaches, which migrates the system to have a services-oriented focus without incorporating general objected-oriented (OO) or functional oriented feature. In this study, a case study and information capacity theory were employed to verify/validate that this approach is indeed an effective and a practicable one.

IT systems perspective - The state of web services

Web services-based systems architectures could allow for the decomposition of a business process and its applications into modules that communicate and interact with one another. Effectively decoupling these software modules to make them more independent and properly encapsulating functionality within the modules would have several advantages. However service-provider support, semantic coherence, and workflow management are required for Web services to realize their potential.