Towards Enhanced Program Comprehension for Service Oriented Architecture (SOA) Systems

Service Oriented Architecture (SOA) is an emerging paradigm for orchestrating software components to build new composite applications that enable businesses, government agencies and other organizations to collaborate across institutional boundaries. SOA offers new languages and a variety of software development tools that enable software engineers to configure software as services and to interconnect services with other services independent of differences in operating platform and programming and communicating languages. However, SOA composite applications introduce additional complexity into the construction, deployment and maintenance of software, for the purpose of aggravating the issue of program comprehension, which is at the heart of software maintenance. This article describes the challenges in SOA program comprehension and reports on the results of a two-part case study aimed at identifying information that would help a SOA software maintainer. Analysis of the results indicates a need for higher-level abstractions and visualizations that can enhance conventional text-based search to support SOA program understanding. This paper then reports on several specific abstractions, visualization methods, and the development of an intelligent search tool to enhance comprehension of the relationships and data within a SOA composite application.

基于XML Web Services企业应用体系结构的开发与研究

提出了一种用于开发企业应用系统的基于XMLWebService技术的应用体系结构,这种结构把应用系统看成是满足一定粒度要求的WebServices组件的集合,并且给出了一种利用XML对企业业务进行统一建模配置的方法,同时在此结构上分析了WebServices组件的集成,管理以及一种新的信息传输方式自动事件路由机制。

基于REST Web Services的图书联合目录研究与实现

为了提高图书馆编目业务的工作效率和书目元数据资源共享,结合管理平台的不一致性,展开了图书馆和出版社联合目录的web服务研究。首先介绍了SOA和Web服务的基本概念,结合REST架构的特点,提出了基于REST风格的图书馆和出版社协同编目的web服务方案。详细介绍了系统在服务端和客户端的设计,实现了图书联合编目系统,提高了图书编目的工作效率,并指出了今后的研究内容。

RESEARCH ON REUSE-BASED WEB SERVICES COMPOSITION

Objective To solve the three principal problems for reusing the software components, i.e., existence, discovery and availability principles, web services provided a new solution for reusing and assembling web software or components under distributed environment with a series of XML-based protocols. Methods A 4+1 meta-model between atomic services, such as Sequence, Parallelism, Alternation, Substitute and Iteration, and a kind of service composition description language in composition process are investigated. Furthermore, an architecture-based service composition model with Ontology Engine is proposed, which is based on the software architecture life-cycle model and provides a mechanism for services composition with dynamic management and deployment. Results The results of the prototype system development show that the service-composed application not only reused the web service components, but also reused the data resources located in distributed databases. Conclusion The method of reused-based web services composition observably decreases the period and cost of development and greatly improves the programming efficiency.

A Workflow-Based Failure Recovery in Web Services Composition

In previous researches in the field of supporting reliability and fault tolerance in web service composition, only low level programming constructs such as exception handling (for example in WSBPEL) were considered. However we believe that the reliability and fault tolerance for composite services must be handled at a higher level of abstraction, i.e. at the workflow level. Therefore a language and technology independent method for fault-tolerant composition of web services is needed. To do this, a fault tolerant workflow is built in which the execution order of the services is determined such that upon a service failure a recovery process with the lowest cost is started. The cost of a service failure includes the cost of failed service and the total costs of roll-baking the previously executed services which are dependent on the failed service. In this article a FSP language is applied to formally specify the workflow.

基于J2EE Web Services的SSO系统的研究与设计

通过研究和探讨J2EE Web服务技术,建立了中小企业信息化服务平台中的SSO系统。利用基于MVC的Struts技术实现了系统的架构;通过采用基于Session的用户会话跟踪技术,实现了统一认证服务的认证令牌;采用基于SSL的安全机制,保护了数据在传输时的完整性;另外,还研究了使用Web服务技术来进行各应用子系统的集成,实现了各应用子系统统一用户身份的认证。

Implementation Method of Non-Intrusive Monitoring Mechanism for Web Services Testing

In web services testing, accessing the interactive contents of measured Services and the information of service condition accurately are the key issues of system design and realization. A non-intrusive solution based on axis2 is presented to overcome the difficulty of the information retrieval in web service testing. It can be plugged in server side or client side freely to test pre-deployed or deployed web services. Moreover, it provides a monitoring interface and the corresponding subscription publication mechanism for users based on web services to support the quality assurance grounded on service-oriented architecture （SOA） application service.

Performance Aware Service Pool in Dependable Service Oriented Architecture

As a popular approach to dependable service oriented architecture （SOA）, a service pool collects a set of services that provide the same functionality by different service providers for achieving desired reliability. However, if the tradeoff between reliability and other important qualities, e.g., performance, has to be considered, the construction and management of a service pool become much more complex. In this paper, an automated approach to this problem is presented. Based on the investigation of service pools in the typical triangle SOA model, two challenges critical to the effectiveness and efficiency of service pools are identified, including which services should be held by a pool and what order these services are invoked in. A set of algorithms are designed to address the two challenges and then a service pool can be automatically constructed and managed for given reliability and performance requirements in polynomial time. The approach is demonstrated on a J2EE based service platform and the comparison results between different pooling algorithms are evaluated.

An OGC standard-oriented architecture for distributed coal mine map services

GIS- or CAD-based technology has been widely used for cartographic maps in coal mines, but structural gaps between such maps make it difficult to provide an integrated map service, for any specific purpose, at higher levels. There is no uniform platform that can be used to manage all involved maps. The main reason for this is that datasets are submitted by individual coal mines using their individual, diverse software. No consistent model is used within the software for data abstraction and symbolization. This paper first reviews all the essential specifications concerning OGC (Open Geospatial Consortium) interoperability. Then an OGC standard-oriented architecture is proposed to provide distributed coal mine map services. Within this new architecture the management of spatial data archives, and the integration of coal mine maps, are achieved through the interfaces of geospatial services. Finally an open source geospatial approach is suggested to implement the proposed scheme. A case study of the Huaibei Coal Group is used to demonstrate the proposal.

SOA-based RFID public services infrastructure:architecture and its core services

Radio frequency identification （RFID） has prominent advantages compared with other autoidentification technologies. Combining RFID with network technology, physical object tracking and information sharing can possibly be carried out in an innovative way. Regarding open-loop RFID applications, RFID public services infrastructure （PSI） is presented, PSI architecture is designed, and service modules are implemented, and a demonstrative application system, blood management and traceability system, is studied to verify PSI. Experimental results show the feasibility of the proposed architecture and the usability of PSI framework software.

PESOI: Process Embedded Service-Oriented Architecture

Service-Oriented Architecture (SOA) has drawn significant attention recently, and numerous architecture approaches have been proposed to represent SOA-based applications. The architecture of SOA-based applications is different from traditional software architecture, which is mainly static. The architecture of an SOA-based application is dynamic, i.e., the application can be composed at runtime using existing services, and thus the architecture is really determined at runtime, instead of design time. SOA applications have provided a new direction for software architecture study, where the architecture can be dynamically changed at runtime to meet the new application requirements. This paper proposes a Process-Embedded Service-Oriented Infrastructure to build SOA-based applications. This infrastructure embeds the entire software lifecycle management and service-oriented system engineering into the application developed on this infrastructure. Thus, the users can easily re-develop the applications during operation to meet the changing environments and requirements, through the supports provided by the embedded infrastructure.

Privacy Protection Framework with Defined Policies for Service-Oriented Architecture

Service-Oriented Architecture (SOA) is a computer systems design concept which aims to achieve reusability and integration in a distributed environment through the use of autonomous, loosely coupled, interoperable abstractions known as services. In order to interoperate, communication between services is very important due to their autonomous nature. This communication provides services with their functional strengths, but also creates the opportunity for the loss of privacy. In this paper, a Privacy Protection Framework for Service-Oriented Architecture (PPFSOA) is described. In this framework, a Privacy Service (PS) is used in combination with privacy policies to create privacy contracts that outline what can and cannot be done with a consumer’s personally identifiable information (PII). The privacy policy consists of one-to-many privacy rules, with each rule created from a set of six privacy elements: collector, what, purpose, retention, recipient and trust. The PS acts as an intermediary between the service consumer and service provider, to establish an unbiased contract before the two parties begin sending PII. It is shown how many Privacy Services work together to form the privacy protection framework. An examination of what current approaches to protecting privacy in an SOA environment is also presented. Finally, the operations the PS must perform in order to fulfill its tasks are outlined.

ENTERPRISE INTEGRATION PLATFORM BASED ON SERVICEORIENTED ARCHITECTURE

To achieve information integration, process integration and application integration of enterprise, an enterprise integration platform （EIP） based on service-oriented architecture （SOA） is built. The enterprise integration model depending on encapsulating the business processes as well as the enterprise applications by the neutral and standard web services is presented. The problem how to discover the existed enterprise resources and share them was resolved depending on the mechanism of publishing and discovering the services. The EIP is integrated closely with product lifecycle management （PLM） system so that the process integration as well as orchestration of the business process services is implemented by encapsulating the workflow engine of PLM system. Not only process integration and application integration, but also information integration based on the bill of material （BOM） conversion driven by process are achieved. Finally, an interpretive, qualitative case study on EIP is conducted for this research.

A Service-Oriented Architecture of Cyber-Physical System and Study on Two Key Issues

As the basis of designing and implementing a cyber-physical system (CPS), architecture research is very important but still at preliminary stage. Since CPS includes physical components, time and space constraints seriously challenge architecture study. In this paper, a service-oriented architecture of CPS was presented. Further, a two-way time synchronization algorithm for CPS service composition was put forward. And a formal method, for judging if actual CPS service meets space constraints, was suggested, which was based on space-π-calculus proposed. Finally, a case study was performed and CPS business process designed by the model and the proposed methods could run well. The application of research conclusion implies that it has rationality and feasibility.

A Collaborative Framework for Mould Design Based on Service-Oriented Architecture

Aiming at improving the traditional object-oriented three-layer architecture for collaborative design, a service-oriented framework for mould design is established by adding a Web service layer to decoupling the direct linking of user interface to functional modules,making the system being platform independent and programming language independent,greatly facilitating the reuse of existing software and hardware resources. .NET technology is adopted to implement the framework. An example scenario is introduced to demonstrate how the system works.

Describing Service-Oriented Architecture by Extended Darwin

Describing Service-Oriented Architecture （SOA） is critical in the development of Web based system, in this paper, an approach for describing SOA by extended Darwin is proposed. The requirements for describing SOA, which are different from that of ordinary architecture, are highlighted firstly, and then a solution for extending Darwin is presented. Using the extended Darwin, service components and connectors can be described explicit by the extended construct, as well as precise operational semantics of SOA by the π-calculus. Finally an example of supply-chain management system is given for manifesting the effect of the extended Darwin.

Service-oriented air combat simulation architecture

Service-oriented air combat simulation architecture is proposed.The core design goal is high agility which represents the ability to accommodate the simulation requirements change.Its main idea is to design model units as services that can communicate and interoperate with any other services at runtime.A service is autonomous and is fully defined by a description contract which contains some combination of syntactic,semantic,and behavioral information.Based on the architecture,air combat simulation system can be described as an abstract composition of description contracts.It becomes concrete at run time as services that implement the constituent description contracts are discovered and bind.The whole process is a continuous run-time activity that responds to simulation needs and the availability of services.This provides benefits of implementation transparency and minimal dependency between models.Thus,simulation system can minimize the impact of change on it and increase the overall efficiency to respond to requirements change.