8395605
FLTL-MC: Online High Level Program Analysis for Web Services
Although Java- or .NET- centric technologies are the most commonly used in Web services, they are by no means the only ones in practice. This paper proposes an online finite model checking tool FLTL-MC to check the high level safety and liveness properties in complex distributed web service systems, which can offer both a richer and more natural way to search errors. Liveness properties can specify desirable system behaviors which must be satisfied eventually, but are not always satisfied. Existing software model checkers cannot verify liveness in real code because doing so requires finding an infinite execution that does not satisfy aliveness property. In our proposed model, we adopt the finite linear temporal logic to specify the semantics of the online model checking, use binary instrumentation to obtain the distribute states and apply the FLTL-MC engine to dynamically verify the finite linear temporal logic properties in Web service systems. At last, we investigate the well-known distributed protocol WS-Reliable Messaging to demonstrate its applications and detect some hidden bugs with our prototype system.
5812455
Knowledge Enhanced IT Service Management
To manage the increasing complexity of IT systems and align IT services with business is the main theme of IT Service Management (ITSM). Current ITSM architecture adopts ITU as the framework to integrate silos of operational management tools and configuration information to build an end-to-end solution based on best practices. However, it lacks of a systematic means to address an important aspect of IT operation, i.e., managing the knowledge separated in various tools and experts' minds. In this paper, a novel knowledge-enhanced architecture is proposed to improve the effectiveness and efficiency of ITSM. The essential contribution of this novel architecture is to involve a Knowledge Management Database (KMDB) which provides assistance for knowledge capture, mining, storage and sharing. The paper will discuss an approach of how to construct such a KMDB with motivating scenarios and detailed description of key components. To validate the approach, a prototype system is developed and evaluated by being applied for problem analysis on a Cisco Voice over IP (VoIP) system. The experiment results show a remarkable improvement in the effectiveness and efficiency for practical IT service management operations.
15004157
A Semantic QoS-Aware Discovery Framework for Web Services
Augmenting web services with explicit semantics forms the foundation of Service Oriented Architectures (SOAs) automation. As more and more Semantic Web Services (SWSs) are deployed, similar SWSs could have quite different quality-of-service (QoS) levels. The QoS-aware discovery becomes an important challenge. While some efforts try to solve it via Constraint Programming (CP), they suffer from the purely syntactic matchmaking method. Furthermore, the construction of constraints and the selection of services are completely dependent on the literal translation from QoS descriptions, which increase obstacles to actually apply CP. In this paper, we propose a semantic QoS-aware framework for SWSs discovery by combining the semantic matchmaking and CP. Initially, a QoS ontology is presented to define QoS data into service descriptions. Then the ontology reasoning is adopted to change previous syntactic matchmaking into a semantic way. Through confirming the compatibility of concepts, complex QoS conditions are solved as constraints and a selection algorithm is proposed to obtain the optimal offer. Finally, the prototype implementation of our framework is discussed and a SWSs discovery case is used to illustrate the comprehensive discovery process.
13862518
Low Cost Mechanism for QoS-Aware Re-Planning of Composite Service
To meet the business and user requirements, it is crucial to manage the Quality of Service (QoS) of composite web service. Due to the dynamics nature of the web services, the runtime behavior of web services is likely to differ from the initial estimated one. Therefore, a re-planning to adapt the composite service to the QoS violated services, ensuring the global constraints and preferences will be needed. In this paper, we propose a low cost mechanism for re-planning. Such mechanism is supported by an offline re-planning execution environment and a performance prediction based low cost policy.The experimentations show better performance of the mechanism.
12111515
Algorithm of integrating QFD and TRIZ for the innovative design process
TRIZ, the Russian acronym of the Theory of Inventive Problem Solving, is a useful tool that can solve the problem of "how to do" effectively in the innovative design process, while QFD (Quality Function Deployment) is able to settle the problem of "what to do". Although the potential of using both QFD and TRIZ in the product design process is huge, there are little tools to integrate these two methods effectively. In this research, we describe an algorithm that can integrate QFD and TRIZ effectively for the purpose of the innovative design process. The core of the algorithm is to identify the contradictions in TRIZ by defining rules based on HOQ (House of Quality) in QFD. A software tool called TRIZmatrix is developed based on this algorithm. Application of the algorithm to the case of the airbag problem is studied in detail. The software application and the case study show the advantage of this algorithm for CAI (computer aided innovation) software development.
14513982
An Online Model Checking Tool for Safety and Liveness Bugs
Modern software model checkers are usually used to find safety violations. However, checking liveness properties can offer a more natural and effective way to detect errors, particularly in complex concurrent and distributed e-business systems. Specifying global liveness properties which should always eventually be true proves to be more desirable, but it is hard for existing software model checkers to verify liveness in real codes because doing so requires finding an infinite execution. For solving such a challenge, this paper proposes an online checking tool to verify the safety and liveness properties of complex systems. We adopt the linear temporal logic to describe the semantics of the finite model checking, use binary instrumentation to obtain the distribute states and apply a checking engine to dynamically verify the finite trace linear temporal logic properties. At last, we demonstrate the method in a distributed system using distributed protocol Paxos and achieve good results by experiments.
14872443
Application-aware Interface for SOAP Communication in Web Services
SOAP protocol has emerged as the Web service communication standard. Because of the relatively poor performance, many researchers focus on improving the speed of processing SOAP message. In this paper, we propose SPI, which introduces client usage pattern to the low level SOAP process infrastructure, in order to improve the performance of some kind of Web services applications with specific communication patterns. The pack interface of SPI is an approach to reduce the number of the SOAP messages to improve the latency on client side. This SOAP optimization technique packs concurrent service requests into one SOAP message on client side, and unpacks and executes them on server side. Our implementation and performance study demonstrates the usefulness and effectiveness of the technique
21956342
Architectural design and implementation of highly available and scalable medical system with IBM Websphere middleware
Medical systems require the end-to-end high availability and scalability. There are many components in a medical system, and each individual component contributes to the overall system availability and scalability. We present the formulas to assess the overall system availability and capacity planning, and we architect approaches and technologies to make all components highly available in all tiers by clustering, workload management, and replication. We discuss how to unify all medical systems and design the uniform framework for different kinds of medical systems to hook up with this framework so that we can maintain a highly available and highly scalable system with ease. We use the n-tier distributed component based architecture and J2EE technologies as well as Web services to interact with .NET and others. We discuss how to program in the framework for high availability and scalability and how to upgrade application software without service interruption to achieve continuous availability. We show how to add or reduce hardware capacity in each tier and how to maintain hardware and software without service interruption as well as how to balance the capacity and availability among tiers.
7283306
A Fair Item-Item Exchange Protocol Satisfying Newly Introduced Requirements
Many protocols are designed to guarantee fairness in electronic exchange that is widely used in e-commerce and e-government systems. In spite of the cryptographic view, we tend to view the fairness problem in a more complete vision. First we present a renewed set of requirement definitions for fair protocols. Second we study the encrypted item validation problem and present a simple and effective solution. With these preliminary discussions, we present our new item-item exchange protocol that is the first one to satisfy those newly introduced requirements
9126668
Hand Gesture Tracking for Wearable Computing Systems
A spin stabilized, earth orbitting satellite having a phased array antenna capable of radiating a plurality of steered electromagnetic beams to predetermined earth locations. The antenna array extends around the satellite and is made up of individual elements which are energized through semiconductor diode devices by electron beams. The electron beams are controlled by fields having the same frequency as the spin frequency of the satellite.
14490221
Exploiting Request Characteristics to Improve Performance of Web Services Based Business Applications
Web Services and workflow have been widely adopted in building complicated business systems. In these systems, high security concern is claimed. But frequent authentication and computing-intensive encoding and decoding operation bring extra workload to the systems and greatly impact the performance of Web Services and workflow engine, especially under heavy load. In this paper, we propose Requests Automated Binding Mechanism, RABM, to automatically pack the requests from multiple clients but to a common target service in a short time period into one SOAP message, then sent by the workflow engine at runtime. Extra security operation costs are reduced without modifying of application programs. We use the Travel Service provided by W3C to evaluate RABM. As the experiment result shows, we can achieve up to 130% improvement of throughput and lower the average response time to 41%1.