Bingnan Xiao

Developing and assuring trustworthy Web services

Web services are emerging technologies that are changing the way we develop and use computer systems and software. Current Web services testing techniques are unable to assure the desired level of trustworthiness, which presents a barrier to WS applications in mission and business critical environments. This paper presents a framework that assures the trustworthiness of Web services. New assurance techniques are developed within the framework, including specification verification via completeness and consistency checking, specification refinement, distributed Web services development, test case generation, and automated Web services testing. Traditional test case generation methods only generate positive test cases that verify the functionality of software. The Swiss cheese test case generation method proposed in this paper is designed to perform both positive and negative testing that also reveal the vulnerability of Web services. This integrated development process is implemented in a case study. The experimental evaluation demonstrates the effectiveness of this approach. It also reveals that the Swiss cheese negative testing detects even more faults than positive testing and thus significantly reduces the vulnerability of Web services.

RTSOA: Real-Time Service-Oriented Architecture

This paper extends the traditional service-oriented architecture (SOA) to a new real-time SOA (RTSOA) and proposes a framework for the new architecture, by providing real-time service modeling, design, code generation, simulation, deployment, execution, orchestration, and management. The concepts, architecture, and enabling technique are studied for real-time SOA. In addition, an efficient algorithm is derived in the paper to find the optimal composition of real-time services subject to the real-time constraint

UCSOA: User-Centric Service-Oriented Architecture

This paper introduces a new user-centric service-oriented architecture (UCSOA) that allows end users to compose applications. UCSOA is an extension of consumer-centric service-oriented architecture (CCSOA), which is an extension of conventional SOA. The conventional SOA is producer-centric because service providers publish their services and service consumers must search available services to compose their applications. CCSOA is different as it allows consumers publish their needs including workflows and services, and let producers to produce services to meet the requirements. Based on CCSOA, UCSOA provides support for end users. An application builder is an engineer who has both domain and programming knowledge, while an end user has little knowledge on programming and thus UCSOA needs to allow nontechnical persons to compose their applications. This paper presents the concepts, architecture, enabling techniques, and illustrative examples

Swiss Cheese Test Case Generation for Web Services Testing

Current Web services testing techniques are unable to assure the desired level of trustworthiness, which presents a barrier to WS applications in mission and business critical environments. This paper presents a framework that assures the trustworthiness of Web services. New assurance techniques are developed within the framework, including specification verification via completeness and consistency checking, test case generation, and automated Web services testing. Traditional test case generation methods only generate positive test cases that verify the functionality of software. The proposed Swiss Cheese test case generation method is designed to generate both positive and negative test cases that also reveal the vulnerability of Web services. This integrated development process is implemented in a case study. The experimental evaluation demonstrates the effectiveness of this approach. It also reveals that the Swiss Cheese negative testing detects even more faults than positive testing and thus significantly reduces the vulnerability of Web services.

Pi4SOA: A Policy Infrastructure for Verification and Control of Service Collaboration

This paper proposes a pattern-based service collaboration architecture using services as building blocks in a service-oriented architecture (SOA). In this architecture, service registry is used to obtain the metadata of services and collaboration patterns. Thus, not only services, but also collaboration patterns can be reused. However, dynamic collaboration requires a measure to verify and validate such a dynamic process at the meta-control level. This paper presents a policy-based infrastructure to dynamically verify and control the collaboration process in SOA

Verification Framework for Dynamic Collaborative Services in Service-Oriented Architecture

This paper introduces a dynamic verification framework for collaborative services in service-oriented architecture (SOA). Collaboration plays a critical role in SOA, an effective verification framework for collaboration will greatly reduce the effort for rapid and adaptive service composition and evaluation of applications based on collaborative services. The verification framework provides a service-oriented infrastructure for completeness and consistency analyses, model-checking, simulation, and policy enforcement of process specification based on collaborative services in SOA. The paper presents the concepts, architecture, profiling techniques and illustrative examples that demonstrate the concepts and the techniques

SOA Collaboration Modeling, Analysis, and Simulation in PSML-C

This paper extends the ebXML Web services development framework to introduce a new collaboration framework, which is based on the collaboration specification language PSML-C (Process Specification and Modeling Language for Collaboration), CCSOA (Consumer-Centric Service-Oriented Architecture), and DDSOS (Dynamic Distributed Service-Oriented Simulation) framework. Since collaborations are inevitable and play a critical role in SOA, an effective framework will greatly reduce the effort for rapid and adaptive service composition, simulation, evaluation, and collaboration. The PSML-C collaboration framework provides a service-oriented infrastructure for process collaboration specification, modeling, design, code generation, simulation, deployment, execution, and management. This paper presents the concepts, architecture, enabling techniques, and illustrative examples that demonstrate the concepts and the techniques

Roadmap to a Full Service Broker in Service-Oriented Architecture

Service-broker is an important mechanism in service-oriented architecture (SOA), which facilitates service registration, publication, and discovery. UDDI and ebXML are two major standards that implement service brokerage by providing service registry and service repository. As SOA applications become pervasive, the need for more powerful service broker becomes a necessity. This paper explores the features, criteria of the future service brokers that can meet the increasing needs in SOA software development.

Collaboration Policy Generation in Dynamic Collaborative SOA

Governance by policies is an important feature in service-oriented architecture (SOA). This paper introduces a collaboration policy generation technique to govern dynamic collaboration in SOA systems. Dynamic collaboration allows two parties not knowing each other establish their collaboration protocol at runtime. Traditional SOA allows parties to collaborate but with a known collaboration protocol before execution. In dynamic collaboration, as collaboration protocols will be negotiated and determined at runtime, policies need to be generated at runtime to manage the interaction. This paper presents the concepts, architecture, and illustrative examples that demonstrate the dynamic collaboration policy generation technique

Collaborative software design in an SOA environment

Based on the current Service-Oriented Architecture (SOA), this paper proposes a new collaborative software design methodology in an SOA Environment: the Global Software Enterprise (GSE). The current SOA is producer-centric, in which the service providers publish services that they produce and let the consumers to search available services to compose their applications. GSE is build on top of Consumer-Centric SOA (CCSOA), in which the application builders publish their application requirements for the service providers to follow when producing or customizing services to support the application. This new methodology reduces the workload and improves the application description capability of the service consumers. It also extends the capacity of design and code sharing, and thus further improves the software productivity. This paper presents the concepts, architecture, enabling techniques, and illustrative examples of collaborative software design in GSE.