5355145
Non-Repudiation and Fairness in Electronic Data Exchange
In this paper we discuss the two security issues: non-repudiation and fairness in association with e-commerce applications. In particular, these issues are addressed in the context of electronic data exchange, which is one of the most commonly seen e-commerce applications. In detail, this paper gives a survey of the approaches to non-repudiation and fair electronic data exchange protocols. We additionally discuss the current technologies that propose solutions to these issues, and the emerging standards in the area of business data formats and protocols for the exchange of such data. Finally, we discuss the architecture layer at which to implement the protocols for non-repudiation and fair data exchange.
1884872
A mobility monitoring based advance reservation protocol
Future wireless cellular networks will be Internet Protocol (IP) based. Users of wireless devices in these networks will expect to run real-time applications that require guarantees of Quality of Service (QoS). Such a user will expect the same seamless QoS that he would receive if he were running real-time applications on a wired network. Achieving seamless QoS in a mobile environment implies that a reservation should be re-established at the new Base Station (BS) before hand-over occurs. However, making these advance reservations is wasteful of valuable bandwidth in the wireless network. This paper proposes a protocol, called the Mobility Monitoring Based Advance Reservation Protocol (M²BARP), which aims to reduce the bandwidth overhead of making advance reservations. The protocol makes use of information about a Mobile Node's (MN) mobility to make a single advance reservation when the MN is about to hand-over. Unlike previous work, M²BARP takes advantage of overlapping cells to help to provide a more seamless QoS by reducing the number of calls dropped at hand-over
42027884
New Approximation for Minimum-Weight Routing Backbone in Wireless Sensor Network
Our problem formulation is as follows. Given a weighted disk graph Gwhere the weight of edge represents the transmission energy consumption, we wish to determine a dominating tree Tof Gsuch that the total weight of edges in Tis minimized. To the best of our knowledge, this problem have not been addressed in the literature. Solving the dominating tree problem can yield a routing backbone for broadcast protocols since: (1) each node does not have to construct their own broadcast tree, (2) utilize the virtual backbone to reduce the message overhead, and (3) the weight of backbone is minimized. 
 
Our contributions to this problem is multi-fold: First, the paper is the first to study this problem, prove the hardness of this problem and propose an approximation framework. Second, we present a heuristic to approximate the solution with low time complexity. Third, a distributed algorithm is provided for practical implementation. Finally, we verify the effectiveness of our proposal through simulation.
14935404
Levels of Authentication Assurance: an Investigation
The ES-LoA project, funded by the UK Joint Information Systems Committee (JISC) under its e- Infrastructure Security Programme, investigates current and future needs among UK research and education community for a more fine-grained authorisation scheme that would allow service providers to take into account of the levels of confidence in identifying a remote entity requesting for service access. Such a fine-grained authorisation scheme is attractive to service providers offering resources with varying levels of sensitivity and/or wishing to tailor their security protections based upon risk levels. Service providers may wish to restrict access to more sensitive resources only to those who have gone through a more stringent authentication process, or given the same remote entity, require the use of a stronger authentication token should the access request come from a more risky environment. In this way, the quality of an authentication instance, expressed as an authentication Level of Assurance (LoA), becomes one of the parameters used in access control decision making. This paper investigates the current worldwide efforts in defining LoA and identifies gaps in existing definitions when they are applied to a federated environment.
1660866
A General Fuzzified CMAC Controller with Eligibility
This paper presents an online neural network controller. Cerebellar Model Articulation Controller (CMAC) is suitable to online control due to its fast learning speed. By integrating the CMAC address scheme with fuzzy logic concept, a general fuzzified CMAC (GFAC) is proposed. Then by incorporating the concept of eligibility into the GFAC, a GFAC controller with eligibility is presented, named FACE. A learning algorithm for the FACE is derived to tune the model parameters. To achieve online control, an efficient implementation of the proposed FACE method is presented. As an example, the proposed FACE is applied to a ship steering control system. The simulation results show that the ship course can be properly controlled under the disturbances of wave, wind and current.
14654466
A Purpose-Based Access Control Model
Achieving privacy preservation in a data-sharing computing environment is a challenging problem. The requirements for a privacy preserving data access policy should be formally specified in order to be able to establish consistency between the privacy policy and its purported implementation in practice. Previous work has shown that when specifying a privacy policy, the notion of purpose should be used as the basis for access control. A privacy policy should ensure that data can only be used for its intended purpose, and the access purpose should be compliant with the data's intended purpose. This paper presents a mechanism to specify privacy policy using VDM. The entities in the purpose-based access control model are specified, the invariants corresponding to the privacy requirements in privacy policy are specified, and the operations in the model and their proof obligations are defined and investigated.
16171710
An Analysis Framework of Factors Influencing China Software and Information Service Offshore Outsourcing
Offshore outsourcing has become popular because of cost or skill advantage. China is considered as one of major global software and information service offshore destinations, but it cannot compete with India right now. Based on literature review, this paper first presents an overview of the industry. Then 38 service providers in China are investigated to give a firm-level analysis of the industry. A framework of factors influencing the industry is presented. Influence factors are classified into macro factors, middle factors, and micro factors, each of which is analyzed in detail. It is concluded that China software and information service offshore outsourcing industry is of great potential, but needs marketing and advertising.
35884730
Compact access control labeling for efficient secure XML query evaluation
Fine-grained access controls for XML define access privileges at the granularity of individual XML nodes. In this paper, we present a fine-grained access control mechanism for XML data. This mechanism exploits the structural locality of access rights as well as correlations among the access rights of different users to produce a compact physical encoding of the access control data. This encoding can be constructed using a single pass over a labeled XML database. It is block-oriented and suitable for use in secondary storage. We show how this access control mechanism can be integrated with a next-of-kin (NoK) XML query processor to provide efficient, secure query evaluation. The key idea is that the structural information of the nodes and their encoded access controls are stored together, allowing the access privileges to be checked efficiently. Our evaluation shows that the access control mechanism introduces little overhead into the query evaluation process.
9362943
Finding shortest paths in large network systems
This paper describes a disk-based algorithm for finding shortest paths in a large network system. It employs a strategy of processing the network piece by piece and is based on new algorithms for graph partitioning and for finding shortest paths that overcome the problem of existing approaches. To show that it is scalable to large network systems and is adaptable to different computing environments, seven states in Tiger/Line files are extracted as test cases and are experimented on machines with different configurations. The running time for finding the shortest path depends primarily on the power of the underlying systems. Moreover, to run the algorithm optimally, the memory requirement is not large, even for a very large network system such as the road system in several states in Tiger/Line file. To evaluate its performance, New Mexico state road system is used as the test case, and is compared with Dijkstra's algorithm. The average running time of the proposed algorithm is, in the worst case, about two and a half times slower than that of Dijkstra's algorithm; provided that in Dijkstra's algorithm, the whole graph can be fit into main memory and is already loaded in advance. If the I/O time for loading the whole graph is counted, the proposed algorithm is faster in essentially all cases.
62212730
Distributed supercomputing to achieve real-time representation and manipulation of complex scenes
Abstract Besides the ray tracing technique, the radiosity method is another major approach for global illumination modeling in the field of computer graphics. Since this method needs a huge amount of storage space (both memory and disk) and a long pre-computation cycle, it is not suitable to implement it on conventional workstations. Supercomputers seem to be necessary for such kind of graphics applications. However, some problems appear with the integration of supercomputers and workstations in a distributed computing environment, especially for graphics application. The major problems are: (i) unavailability of standard higher-level mechanisms for building distributed application; (ii) transparent access to supercomputers without remote login or file transfer sessions; (iii) computation balance to make the best use of the performance of supercomputers and workstations; (iv) data transfer/storage strategy between supercomputers and workstations; and (v) conflict between interaction and response time for graphics applications. In this paper we suggest solutions to the above mentioned problems based on the remote procedure call (RPC) and the client/server model, for the radiosity package implementation. After the introduction of the radiosity method, we concentrate on the integration between supercomputers and high-performance workstations. We also convey some general issues related to distributed computing and present the experience with our implementation, such as the application protocol definition, error recovery, code debugging etc. The radiosity package has been implemented at ZGDV in Darmstadt, F.R.G. in a network environment including a Multiflow TRACE 7/300 supercomputer connected to several VAX, SUN and HP workstations.
6932463
BlossomTree: evaluating XPaths in FLWOR expressions
Efficient evaluation of path expressions has been studied extensively. However, evaluating more complex FLWOR expressions that contain multiple path expressions has not been well studied. In this paper, we propose a novel pattern matching approach, called BlossomTree, to evaluate a FLWOR expression that contains correlated path expressions. BlossomTree is a formalism to capture the semantics of the path expressions and their correlations. We propose a general algebraic framework (abstract data types and logical operators) to evaluate BlossomTree pattern matching that facilitates efficient evaluation and experimentation. We design efficient data structures and algorithms to implement the abstract data types and logical operators. Our experimental studies demonstrate that the BlossomTree approach can generate highly efficient query plans in different environments.