14598540
Modelling Strategic Actor Relationships to Support Intellectual Property Management
In today's increasingly knowledge-intensive economy, patents and other forms of intellectual property mechanisms are widely used to protect inventions, generate revenue, and build strategic alliances. Techniques from conceptual modelling can be used to analyze the structure of knowledge, highlighting crucial entities and relationships. However, to analyze the strategic significance of particular pieces or bodies of knowledge within an organizational and business context, we need an ontology that captures the social and intentional dimensions of knowledge management. In this paper, we outline the use of the i* strategic actor relationships modelling framework to support IP management. In i*, actors have goals, and know-how and resources for achieving goals. Patents restrict the use of know-how, thus prompting actors to reposition themselves within a network of dependency relationships. Examples from the e-commerce domain are used to illustrate.
10661094
Designing information systems in social context: a goal and scenario modelling approach
In order to design a better information system, a designer would like to have notations to visualize how design experts' know-how can be applied according to one's specific social and technology situation. We propose the combined use of a goal-oriented requirements language (GRL) and a scenario-oriented notation Use Case Maps (UCM) for representing design knowledge of information systems. Goal-oriented modelling is used throughout the requirements and design process. In GRL, goals are used to depict business objectives and system requirements, both functional and non-functional. Tasks are used to represent different ways for achieving goals. Means-ends reasoning is used to explore alternative solutions and their operationalizations into implementable system constructs. Social context is modelled in terms of dependency relationships among agents and roles. Scenarios expressed in UCM are used to describe elaborated business processes or workflow. The complementary use of goal-oriented modelling with GRL and scenario modelling with UCM is illustrated with an example of designing a web-based training system.
2115447
Security and privacy requirements analysis within a social setting
Security issues for software systems ultimately concern relationships among social actors stakeholders, system users, potential attackers - and the software acting on their behalf. We propose a methodological framework for dealing with security and privacy requirements based on i*, an agent-oriented requirements modeling language. The framework supports a set of analysis techniques. In particular, attacker analysis helps identify potential system abusers and their malicious intents. Dependency vulnerability analysis helps detect vulnerabilities in terms of organizational relationships among stakeholders. Countermeasure analysis supports the dynamic decision-making process of defensive system players in addressing vulnerabilities and threats. Finally, access control analysis bridges the gap between security requirement models and security implementation models. The framework is illustrated with an example involving security and privacy concerns in the design of agent-based health information systems. In addition, we discuss model evaluation techniques, including qualitative goal model analysis and property verification techniques based on model checking.
8242993
Designing Web-Based Systems in Social Context: A Goal and Scenario Based Approach
In order to design a better web-based system, a designer would like to have notations to visualize how design experts’ know-how can be applied according to one’s specific social and technology situation. We propose the combined use of a goal-oriented language GRL and a scenarios-oriented notation UCM for representing design knowledge of web-based systems and information systems in general. Goals are used to depict business objectives, functional and non-functional system requirements. Tasks are used in the exploration of alternative technologies and their operationalizations into system constructs. Actors are used to do role-based analysis on social relationships. Scenarios are used to describe elaborated business processes or workflow. The approach is illustrated with an example of designing a web-based training system.
3582970
Building a Semantic Web System for Scientific Applications: An Engineering Approach
This paper presents an engineering experience for building a Semantic Web compliant system for a scientific application – agricultural zoning. First, we define the concept of ontological cover and a set of relationships between such covers. These definitions, based on domain ontologies, can be used, for example, to support the discovery of services on the Web. Second, we propose a semantic acyclic restriction on ontologies which enables the efficient comparison of ontological covers. Third, we present different engineering solutions to build ontology views satisfying the acyclic restriction in a prototype. Our experimental results unveil some limitations of the current Semantic Web technology to handle large data volumes, and show that the combination of such technology with traditional data management techniques is an effective way to achieve highly functional and scalable solutions.
2383268
Efficient Formation of Edge Cache Groups for Dynamic Content Delivery
Cost-effective cooperation among a network of edge caches is widely accepted as an effective mechanism for enhancing the scalability, performance, and reliability of edge cache networks. However, the problem of how to form cache groups for achieving effective and efficient cooperation in edge cache networks has largely been unexplored. In this paper, we identify two important factors that need to be considered while forming cooperative groups, namely, network proximities of edge caches and network distances of the caches to the origin server. We propose two novel cache clustering schemes for accurately partitioning the caches of a given edge cache network into specified number of cache groups. The first scheme, called the Selective Landmarks scheme (SL scheme), accurately partitions the edge cache network into cooperative groups based on the network proximities of the caches. The second cache group formation scheme, called Server Distance sensitive Selective Landmarks scheme (SDSL scheme), provides a careful combination network proximities and server distances. Our experiments indicate that the proposed techniques can yield significant performance benefits.
18178349
TAM: a system for dynamic transactional activity management
Electronic commerce (EC) has remarkably reshaped today's business practices. The logic embedded in business transactions are becoming more exible and sophisticated; the number of components within these business transactions are fastly increasing; and business transactions are getting more distributed and interactive as well. These, on the other hand, make today's business applications more vulnerable to resource availability constraints and consistency problems due to failures. For example, network congestion, server overload, user absence, and other exceptions all might cause temporary or permanent bottlenecks to ongoing business work ows. Developing system support to make work ow activities more reliable, e cient, and adaptive to changes or exceptions therefore poses important yet challenging questions that call for practical solutions. The TAM project at OGI aims at developing a exible framework and algorithms that address these challenges. Comparing with other research e orts, our approach is unique in that we combine advanced transaction processing (TP) technologies with adaptive methods to guide our system design, and build the mechanisms by extending the functions of current TP systems. On the theoretical side, we have developed a Transactional Activity Model (TAM) for the speci cation and management of activities with transactional properties. TAM is a careful combination of a compositional activity model [5] with well-de ned extended transaction models (ETMs) [3] such as split/join transactions [9]. It provides simple and effective speci cation facilities that allow business process designers to specify the behavioral composition and re nement
18654729
Reliable peer-to-peer end system multicasting through replication
A key challenge in peer-to-peer computing system is to provide decentralized and yet reliable services on top of a network of loosely coupled, weakly connected and possibly unreliable peers. This work presents an effective dynamic passive replication scheme designed to provide reliable multicast service in peer-cast, an efficient and self-configurable peer-to-peer end system multicast (ESM) system. We first describe the design of a distributed replication scheme, which enables reliable subscription and multicast dissemination of information in an environment of inherently unreliable peers. Then we present an analytical model to discuss its fault tolerance properties, and report a set of initial experiments, showing the feasibility and the effectiveness of the proposed approach.
1882687
Securing decentralized reputation management using TrustGuard
Reputation systems have been popular in estimating the trustworthiness and predicting the future behavior of nodes in a large-scale distributed system where nodes may transact with one another without prior knowledge or experience. One of the fundamental challenges in distributed reputation management is to understand vulnerabilities and develop mechanisms that can minimize the potential damages to a system by malicious nodes. In this paper, we identify three vulnerabilities that are detrimental to decentralized reputation management and propose TrustGuard--a safeguard framework for providing a highly dependable and yet efficient reputation system. First, we provide a dependable trust model and a set of formal methods to handle strategic malicious nodes that continuously change their behavior to gain unfair advantages in the system. Second, a transaction-based reputation system must cope with the vulnerability that malicious nodes may misuse the system by flooding feedbacks with fake transactions. Third, but not the least, we identify the importance of filtering out dishonest feedbacks when computing reputation-based trust of a node, including the feedbacks filed by malicious nodes through collusion. Our experiments show that, comparing with existing reputation systems, our framework is highly dependable and effective in countering malicious nodes regarding strategic oscillating behavior, flooding malevolent feedbacks with fake transactions, and dishonest feedbacks.