A three-layer architecture for e-contract enforcement in an e-service environment
In an e-service environment, contracts are important for attaining business process interoperability and enforcing their proper enactment.  In the document layer, contracts are composed of different types of clauses. In the business layer, e-contract enforcement activities are defined through the realization of contract clauses as business rules in event-condition-action (ECA) form. In the implementation layer, cross-organizational e-contract enforcement interfaces are implemented with contemporary Enterprise Java Bean and Web services. We present a methodology for the engineering of e-contracts enforcement from a high-level document-view down to the implementation layer based on this architecture, using a supply-chain example. As a result, e-contracts can be seamlessly defined and enforced. Conceptual models of various layers are given in the Unified Modeling Language (UML).

title: Parallel Algorithm Design for Workstation Clusters
abstract: Clusters of workstations connected by local area networks are in common use in many organizations. The combined processing power of these clusters is rarely exploited owing to the lack of suitable parallel algorithms. The paper describes a parallel programming paradigm called supervisor-worker, suitable for the workstation environment, which can be used to speed up the execution of a large class of existing sequential programs. Simple formulae are developed to predict the speed-up of a parallel algorithm developed in this way. The predictions depend on two easily-determined parameters of the sequential program and the characteristic communication cost of the workstation cluster. Consequently, it is possible to estimate the benefits of the parallel program before proceeding with detailed implementation. As an example, the parallel version of a travelling salesman program is developed and the measured speed-up compared with the predicted speed-up.

title: An event driven approach to customer relationship management in e-brokerage industry
abstract: Customer relationship management (CRM) is critical to the success of a business. Recent work in CRM has focused on the mining of customer-related data and the construction of customer behavior models. In this paper, we present a framework for an effective detection of business events that trigger the execution of customer-related activities based on a set of predefined business rules. An event is the occurrence of something interesting to the system itself or to user applications. Event driven execution of rules in event-condition-action (ECA) form can ensure efficiency and timeliness. This is an important aspect of CRM that few researchers have reported. In the e-brokerage industry, business events concern mainly with clients, brokerage firms and the stock market environment. Business events due to the clients include order placement, complaints filing, service exceptions, and change of personal profiles. Business events due to the brokerage firms include staff turnovers and amendment of e-brokerage services. Business events due to the environment include market news and fluctuation of stock prices. An event-driven CRM prototype implementing the proposed framework has been successfully applied to support an e-brokerage system. The prototype integrates a client portal, a call center, a managerial application, external event detectors and an analysis engine. There is little room in Hong Kong's stock brokerage industry for a brokerage firm to increase its revenue through cross- or up-sale trading. The key success factor of a brokerage is therefore its ability to retain existing clients and to increase their satisfaction through effective coordination and enactment of CRM activities.

title: A Three-Layer Framework for Cross-Organizational e-Contract Enactment
abstract: In an e-commerce environment, contracts are important for attaining business process interoperability and enforcing their proper enactment.  In the business layer, e-contracts are defined through analyzing the contract clauses to business rules and business entities. In the structural layer, requirements for the E-contract enactment workflow are elucidated through requirement analysis to cover both static and dynamic aspects. In the implementation layer, workflows and cross-organizational interoperating interfaces are implemented using contemporary Enterprise Java Bean and Web services. In this paper, we present the methodology and process for engineering the functional aspects of e-contracts from high-level business-view down to implementation layer based on this framework, illustrated with an investment example. The framework allows an e-contract to be seamlessly defined and enacted. The framework is modeled in UML.

title: Developing e-Negotiation Process Support by Web Services

title: Checking subsystem safety properties in compositional reachability analysis
abstract: The software architecture of a distributed program can be represented by an hierarchical composition of subsystems, with interacting processes at the leaves of the hierarchy. Compositional reachability analysis has been proposed as a promising automated method to derive the overall behavior of a distributed program in stages, based on its architecture. The method is particularly suitable for the analysis of programs which are subject to evolutionary change. When a program evolves, only behavior of those subsystems affected by the change need be re-evaluated. The method however has a limitation. The properties available for analysis are constrained by the set of actions that remain globally observable. The properties of subsystems, may not be analyzed. We extend the method to check safety properties of subsystems which may contain actions that are not globally observable. These safety properties can still be checked in the framework of compositional reachability analysis. The extension is supported by augmenting finite-state machines with a special undefined state /spl pi/. The state is used to capture possible violation of the safety properties specified by software developers. The concepts are illustrated using a gas station system as a case study.

title: Modeling multistep cyber attacks for scenario recognition
abstract: Efforts toward automated detection and identification of multistep cyber attack scenarios would benefit significantly from a methodology and language for modeling such scenarios. The Correlated Attack Modeling Language (CAML) uses a modular approach, where a module represents an inference step and modules can be linked together to detect multistep scenarios. CAML is accompanied by a library of predicates, which functions as a vocabulary to describe the properties of system states and events. The concept of attack patterns is introduced to facilitate reuse of generic modules in the attack modeling process. CAML is used in a prototype implementation of a scenario recognition engine that consumes first-level security alerts in real time and produces reports that identify multistep attack scenarios discovered in the alert stream.

title: Efficient video similarity measurement with video signature
abstract: The proliferation of video content on the Web makes similarity detection an indispensable tool in Web data management, searching, and navigation. We propose a number of algorithms to efficiently measure video similarity. We define video as a set of frames, which are represented as high dimensional vectors in a feature space. Our goal is to measure ideal video similarity (IVS), defined as the percentage of clusters of similar frames shared between two video sequences. Since IVS is too complex to be deployed in large database applications, we approximate it with Voronoi video similarity (VVS), defined as the volume of the intersection between Voronoi cells of similar clusters. We propose a class of randomized algorithms to estimate VVS by first summarizing each video with a small set of its sampled frames, called the video signature (ViSig), and then calculating the distances between corresponding frames from the two ViSigs. By generating samples with a probability distribution that describes the video statistics, and ranking them based upon their likelihood of making an error in the estimation, we show analytically that ViSig can provide an unbiased estimate of IVS. Experimental results on a large dataset of Web video and a set of MPEG-7 test sequences with artificially generated similar versions are provided to demonstrate the retrieval performance of our proposed techniques.

title: An Architecture for an Adaptive Intrusion-Tolerant Server
abstract: We describe a general architecture for intrusion-tolerant enterprise systems and the implementation of an intrusion-tolerant Web server as a specific instance. The architecture comprises functionally redundant COTS servers running on diverse operating systems and platforms, hardened intrusion-tolerance proxies that mediate client requests and verify the behavior of servers and other proxies, and monitoring and alert management components based on the EMERALD intrusion-detection framework. Integrity and availability are maintained by dynamically adapting the system configuration in response to intrusions or other faults. The dynamic configuration specifies the servers assigned to each client request, the agreement protocol used to validate server replies, and the resources spent on monitoring and detection. Alerts trigger increasingly strict regimes to ensure continued service, with graceful degradation of performance, even if some servers or proxies are compromised or faulty. The system returns to less stringent regimes as threats diminish. Servers and proxies can be isolated, repaired, and reinserted without interrupting service.

title: Detecting Disruptive Routers in Wireless Sensor Networks
abstract: In wireless sensor networks, sensor nodes are typically resource constrained and used as routers to forward packets for other nodes. Compromised sensor nodes may be able to cause network-wide denial of service by dropping or corrupting packets. This paper presents a novel, lightweight approach for detecting disruptive routers that drop or corrupt packets.

title: Mesh Permutation Routing with Locality
abstract: Given the permutation routing problem on mesh-connected arrays with a known maximum distance, d, between any source- destination pair, we show how sorting and the greedy algorithm can be combined to yield a deterministic, asymptotically optimal algorithm for solving the problem. This simple algorithm runs in d+O(df(d)) time and requires an O(f;(d)) buffer size (or O(d) time and constant buffer size if we choose f(d) to be a constant). It also gives efficient solutions to the k-k routing problem with locality.