Dongcai Shi

Exploring a Semantic Publish/Subscribe Middleware for Event-Based SOA

Service Oriented Architecture is currently regarded as the next step for software architectures and achieve great usage in web services. However, the traditional SOA uses request/response pattern and is not suit for loose coupling, asynchronous scene while Even-Driven Architecture works well. To support the effective execution of possibly distributed and completely decoupled and heterogeneous services, synchronously or asynchronously executed in an efficient manner, there is an urgent need to integrate EDA and SOA into the next generation of SOA. We propose a semantic publish/subscribe system called JTangPS to serve as the event platform for event based SOA to satisfy the new challenges.

JTangCSPS: A composite and semantic publish/subscribe system over structured P2P networks

Publish/subscribe systems offer a loosely coupled communication paradigm in distributed information systems. However, supporting expression of semantic events, expression of logical and temporal patterns of composite events, and how to manage and route composite events and subscriptions still need further research. In this paper, we present the design and implementation of JTang composite and semantic publish/subscribe system over structured P2P networks, and highlight its novel features, including semantic broker network, composite event and subscription language and distributed composite subscription management. The experiments based on the Peersim simulator over the Pastry overlays show that the ontology routing table helps decrease the average number of hops and the use of composite subscriptions significantly reduces the load on the network.

A Peer-to-Peer Approach to Large-Scale Content-Based Publish-Subscribe

Publish-subscribe has become a prevalent paradigm for asynchronous communication in a distributed network. However, existing distributed content-based publish-subscribe systems still have limitations in scalability and adaptability. In this paper, we present a content-based publish-subscribe system over distributed hash table (DHT) based P2P networks. To improve the efficiency of event publication, our approach maps subscriptions and events to rendezvous nodes in terms of a combination of the domain schema identifier and the numbers of attributes in the subscriptions or the events. To impose little overhead on routing substrate, our approach exploits the embedded multicast tree on DHT-based P2P networks for event delivery. The experimental results demonstrate that our system scales well with increasing number of peers and large numbers of subscribers and events

Software Product Line Oriented Feature Map

The core idea of software product line engineering is to develop a reusable infrastructure that supports the software development of a family of products. On the base of domain analysis, feature modeling identifies commonalities and variability of software products in terms of features to provide an acknowledged abstract to various stakeholders. The concept of feature map is proposed to perfect feature model. It supports customized feature dependencies and constraint expresses, provides the capability to navigate and locate the resource entities of features. Ontology is introduced as the representation basis for the meta-model of feature maps. By the means of selecting features to construct the reusable infrastructure, the components of feature implementation are rapidly located and assembled to produce a family of software products meeting certain dependencies and constraints.

An RDF-Based Publish/Subscribe System

Publish/subscribe is a promising paradigm with a growing appeal in building large-scale distributed applications. Existing publish/subscribe systems have limited support for semantic information. In this paper, we propose JTangPS (JTang Publish/subscribe System), an RDF (Resource Description Framework) based publish/subscribe system which uses RDF graphs to describe events and RDF graph patterns to represent subscriptions. A fast graph-based matching algorithm is presented to reconcile the conflict of expressiveness and scalability. Experimental results using synthetic workload demonstrate the scalability of system with large numbers of subscriptions.

JTangPS: Content-Based Publish/Subscribe over Structured P2P Networks

Publish/subscribe systems have been adopted by many distributed applications to deliver data from publishers to subscribers in an anonymous fashion. However, existing content-based publish/subscribe systems suffer from limitations in scalability. This paper introduces a novel architecture for implementing a content-based publish/subscribe system, called JTangPS, on top of structured P2P networks. JTangPS achieves scalability by mapping subscriptions and events to rendezvous nodes in terms of the combination of domain schema identifier, number of attributes and the first attribute name in the subscription or event. JTangPS enhances routing efficiency by exploiting the embedded multicast tree on P2P networks and by aggregating event delivery messages. Experimental results using a variety of synthesis datasets demonstrate the scalability of system with large numbers of users.

Feature configuration modeling and problem solving for software product line

Software product line is an effective way to implement software production for mass customization. How to organize and configure the feature set in the feature model of software product line to rapidly produce customized software product meeting individual demands is one of the key problems. Corresponding to the phases of feature selection in the process of software production, the feature configuration model is constructed to provide a uniform framework of constraint description for feature model and domain application requirement. The results of problem solving are the sets of feature meeting feature constraints and application requirements. The proposed method of configuration modeling and problem solving provide a theoretical foundation to rapidly produce software product on the base of configuration of reusable domain assets.

Implementation of Interceptor Based Resource Server for Software Product Line

The responsibility of resource server is to store and manage the reusable and product-specific assets produced in the process of software development applying software product line principals. Separately designed for each specific resource type, classical resource server could not satisfy the demands for mass storage of various resource types in collaborative development environment. Interception design pattern is introduced as a novel means to implement resource server. Interceptors with specific functionalities are developed and configured for various resource types in domain to provide a uniform framework to deal with distinct types of resource, including customized resource type. The description of the resource handling process using Pi calculus demonstrates the validity of the approach.

A workflow-based distributed multidisciplinary design optimization framework

In this paper, we propose a generic framework for multidisciplinary design optimization application, which incorporates several existing technologies such as workflow, agent, adapter, Web and XML workflow is used to allow the designer to construct complex branching and iterative MDO problem formulations and automate the design process execution. Agent is employed to manage and coordinate the operations on system resources, and more significantly perform the dynamic load balancing among a cluster of computers. Adapter is integrated to encapsulate commercial or noncommercial engineering tools to provide the designer with uniform interfaces. Web enables the geographically distributed experts to solve a multi-disciplinary problem cooperatively. XML is used to exchange data between adapters and applications. A Java-based prototype system implementation of the proposed MDO framework is presented.