Jen-Yao Chung

S/390 cluster technology: Parallel Sysplex

This paper describes a clustered multiprocessor system developed for the general-purpose, large-scale commercial marketplace. The system (S/390e Parallel Sysplex™) is based on an architecture designed to combine the benefits of full data sharing and parallel processing in a highly scalable clustered computing environment. The Parallel Sysplex offers significant advantages in the areas of cost, performance range, and availability.

A practical approach to Web-based Internet EDI

In traditional business environments, many inter-company processes (such as buying and billing) are performed using paper documents, such as purchase orders and invoices. Electronic data interchange (EDI) allows companies to exchange these documents in a structured and computer-processable format. This helps to automate and streamline business by eliminating or simplifying clerical tasks, speeding information transfer, reducing data errors, and eliminating business processes. Although EDI has been successfully employed in specific industries (such as retail) and in some large enterprises, it has not been widely adopted. The primary barriers to widespread acceptance of EDI are the costs of implementation and the costs of communication, which is frequently done using value-added networks (VANs). These costs are generally too high for companies that do not conduct large numbers of EDI transactions. We introduce a Web-based Internet EDI model that provides valued-added functions traditionally provided by EDI over VANs. In this model, users conduct business transactions using Java-capable browsers instead of traditional EDI software, eliminating the costs of VANs and EDI-related applications.

Composition and evaluation of trustworthy web services

Web service technology seamlessly enables integration of different software to fulfil dynamic business demands in a platform-neutral fashion. By means of standard interfaces, service requesters can obtain their desired functionalities through certain service discovery mechanism, and service providers can offer the functionality to service requesters without exposing details of provided services. However, the adoption of loosely coupled and distributed services will cause trustworthiness problems. In this paper, we use ontology to describe experience and we utilise statistical techniques along with Petri nets to conduct a trustworthy evaluation method for composite web services. The degree of trustworthiness of all involved services in an aggregated composite service will be evaluated by analysing past experiences so that the trustworthiness of the composite service could be estimated.

A framework-based approach to building private trading exchanges

The private trading exchange (PTX) is emerging as the cornerstone of business-to-business e-commerce. At its core, a private trading exchange involves interenterprise integration and collaboration. Our main objective in this paper is to introduce a versatile application platform for building private trading exchanges. This platform supports the management and execution of multienterprise business processes and collaborations in the context of these processes. We review the business requirements of PTX-based systems and the technical challenges in developing such systems. We then examine and categorize the main interaction patterns between the private trading exchange and its participants. These patterns lead to the design of a component framework for process brokering and content aggregation. This framework is the foundation of our application platform for building PTX solutions. We describe the platform and discuss how to use it to implement a PTX solution.

A service management framework for service-oriented enterprises

With a steady pace of adoption of service-oriented architecture, companies have made significant progresses in implementing various kinds of Web services and converting existing applications to service-oriented architecture. As significant number of services have been implemented and put into actual use, many service-oriented enterprises are faced with the problem of how to manage these services in an efficient manner. In this paper, we propose a framework for a more efficient management of these services. In this framework, the creation and maintenance of enterprise solutions are modeled by flows, finite state machines (FSMs) among other formal models. For instance, each enterprise solution would be modeled as composite services that can be described by respective flow and FSM models. These solution models can then be stored, and later retrieved for the execution of these composite services. Furthermore, formal models are also used to maintain and update these service-oriented solutions to improve the efficiency and quality of service management by taking advantage of the underlying service-oriented architecture. In this paper, we first provide a normalized categorization of enterprise services. We then describe the framework for managing services in service-oriented enterprises. We also discuss how this framework can help manage enterprise services more efficiently. Finally, we give a real-world example to illustrate how this framework can be used in practice.

A new approach for context aware SOA

In this paper, a context aware service-oriented architecture is proposed to facilitate service discovery, composition, and verification. There are three main building blocks in this proposed architecture: service verifier, semantic matchmaker, and agent platform. service verifier utilizes Petri nets mechanism to analyze the validity of service description and process model so that no invalid services is published. Semantic matchmaker is designed with the consideration of requesters context to enhance the precision of request-service matchmaking. Agent platform consists of three agents, request agent, broker agent, and service agent to collaborate and execute the entire context aware SOA on behalf of the requesters, matchmaker, and service providers.

Service Discovery in P2P Service-oriented Environments

The P2P service-oriented environment presents new opportunities and challenges for distributed computing and resource sharing. In this paper, we present a middleware infrastructure, called CCSD, for decentralized service discovery in a wide-area ad hoc P2P service-oriented environment. Two of the key ideas of a CCSD P2P network are: 1) the concept of context awareness is extended to the awareness of service capacities of P2P peers, by which peers are able to understand and compare each others service capacities; and 2) a peers capacity context description is replicated in several designated peers in addition to the peer itself. Using a hash table, the description of the most suitable capacity context for a service request can be located quickly and the service request is forwarded to and served at the peer associated with that capacity context. CCSD, designed to satisfy the dynamic and constrained nature of the ad hoc P2P environments, benefits service users in the environments by providing the most suitable service capacity transparently

Assessing existing business data from the World Wide Web

The World Wide Web has experienced phenomenal growth over the last few years. Although, at ifs inception, Web technology was primarily used to retrieve information stored in static documents, important current uses of the Web include retrieval of dynamically changing information and the conducting of business transactions. Such uses of the Web result in access to dynamically changing data on or through Web servers, usually stored in a database. Huge volumes of business data exist on mainframes and other mature platforms that cannot be moved to client/server or workstation-based platforms, due to cost or performance issues. Providing Web access to these legacy data, therefore, is of great commercial interest to businesses. In this paper, we survey several solutions that have been developed to access existing business data through the Web. We discuss the details of two solutions developed at IBM: DB2(R) (DATABASE 2(TM)) World Wide Web Connection and Net.Data(TM). Each of these is a pure middleware approach as opposed to approaches that are integrated with either the Web server or the database management system, which accounts for their flexibility and power.

Performance engineering of a Java-based e-commerce system

The development of enterprise Web applications has evolved from writing servlets using JDBC calls for database access to a component-based paradigm where database access is replaced by calling enterprise JavaBeans (EJB), a Java representation of business objects. Using this component-based paradigm, business logics are encapsulated in coarse-grain session beans, leaving servlets the role of a request dispatcher which converts HTTP requests for servlets into RMI/IIOP requests for session beans and invokes JSP for result presentation. The performance of such a multitier enterprise Web application is dominated by the performance of the EJB. We investigate a model-based approach for performance engineering of multitier enterprise Java applications. A layer queueing model comprising the layers of client applications, session beans, entity beans, and data sources is proposed. By taking into account network latency and RMI overhead, the model can be used to predict the delay-throughput performance of the system and to study issues related to deployment topology. As an example, a layered queueing model is created for an application framework for B2B e-commerce, a real world EJB application. A case study is presented to show the effect of database access delay to the tuning of the connection pool size of data sources.

Solution Templates Tool for Enterprise Business Applications Integration

Todays enterprises must meet the rapidly changing market demands while collaborating with much broader range of trading partners to maximize supply chain efficiency and improve services to customers and their profit margin. To accomplish these business goals, their business application systems, such as enterprise ERP, must integrate and adapt rapidly to meet these business demands and collaborate with other business system without major reimplementation effort. Our proposed approach addresses these problems by using model based approach of creating reusable solution template that consists of off-the-shelf artifacts to be quickly assembled as a solution. In this paper, we introduce a solution template tool that simplifies the life cycle for creating an integration solution, through the flexible design and customization of solution templates, and an interactive environment driven by wizards. By providing levels of abstraction, the proposed tool allows users to compose templates of platform independent model without worrying about implementation details. The tool transforms the composed templates into platform specific IT execution model and a deployable solution, thus easing the task of solution integration lifecycle. A solution template of UCCnet illustrates our study.