Ubicast, an enhanced application-level multicast protocol, is presented in this paper. It is built upon Pastry, a robust and self-organizing peer-to-peer substrate overlay, and leverages its merits of reliable applica...
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Ubicast, an enhanced application-level multicast protocol, is presented in this paper. It is built upon Pastry, a robust and self-organizing peer-to-peer substrate overlay, and leverages its merits of reliable application-level routing and object location. Ubicast is mainly applied to real-time multimedia applications with QoS heterogeneity. It tries to minimize the delay radius of the multicast tree, while meeting different bandwidth requirements. It extends traditional degree-bound model and satisfies nodes' heterogeneous QoS requirements to provide customizable multicast services. Besides, Priority Joining Algorithm based on the concept of potential parents is proposed to limit the number of nodes that a participant needs to probe. The join cost is decreased substantially to guarantee the scalability for a potentially large network topology. Simulation and experimental analysis over large-scale topology confirm the performance improvement of Ubicast which is especially suited for small sized multicast groups.
Based on the adopted redundancy techniques the intrusion-tolerant systems are classified into three kinds: resource redundancy based systems, complete information redundancy based systems, and partial information redu...
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By the discovered correlation between linear functions over GF(q n) and matrices over GF (q), a new scheme is presented to resolve the algebraic expression of Rijndael S-box in this paper. This new scheme has the adva...
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ISBN:
(纸本)1581139551
By the discovered correlation between linear functions over GF(q n) and matrices over GF (q), a new scheme is presented to resolve the algebraic expression of Rijndael S-box in this paper. This new scheme has the advantage of predetermining in the case of a given random base over GF(q n). The reason why only 9 terms are involved in the algebraic expression of Rijndael S-box is presented, which corrects the available inaccurate illustration. We finally conclude all the available methods to determine the algebraic expression of Rijndael S-box. Copyright 2004 ACM.
Publicly verifiable sealed electronic auctions are proposed. The schemes enjoy the following advantages. They require no special trusted parties. After bid opening phase, only the winning price is revealed and the rel...
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In this paper, we introduce an intrusion-tolerant authorization and authentication scheme in distributed environments, by the utilization of a secure multi-party computation scheme by virtue of Feldman's (t+1, n) ...
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In this paper, we introduce an intrusion-tolerant authorization and authentication scheme in distributed environments, by the utilization of a secure multi-party computation scheme by virtue of Feldman's (t+1, n) VSS to perform the warrant authorization. In this way, a warrant can be obtained in a distributed fashion in which any k of registration severs are required to perform the computation. The n segments of the private key of the registration severs set - which are spread across n registration severs - do not have to be recombined on a single machine to perform a warrant authorization. Since kn, the requirement that only k segments are needed inherently provides system reliability.
A family of novel pseudorandom number generators is proposed based on an evolutionary algorithm. These pseudorandom number generators are expressed as EAPRNG. EAPRNGs are driven by some existed simple and unsafe gener...
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A family of novel pseudorandom number generators is proposed based on an evolutionary algorithm. These pseudorandom number generators are expressed as EAPRNG. EAPRNGs are driven by some existed simple and unsafe gener...
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ISBN:
(纸本)0780378040
A family of novel pseudorandom number generators is proposed based on an evolutionary algorithm. These pseudorandom number generators are expressed as EAPRNG. EAPRNGs are driven by some existed simple and unsafe generators which are denoted by mother generators (MG), while outputs of the MGs are hidden by EAPRNGs. The analysis indicates that EAPRNGs are resistant to many known attacks, and that they have good statistical properties, such as uniform probability distribution over GF (2/sup l/) and large periods.
In this paper, the IEEE 802.11 multiple access control (MAC) protocol was modified for use in multi-channel, multi-hop ad hoc networks through the use of a new channel-status indicator. In particular, in the modified ...
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In this paper, the IEEE 802.11 multiple access control (MAC) protocol was modified for use in multi-channel, multi-hop ad hoc networks through the use of a new channel-status indicator. In particular, in the modified protocol, the RTS/CTS dialogue is exchanged on the common access control channel and data packets are transmitted on a selected traffic channel. We have evaluated the improvement due to the multi-channel use and we report in this paper on the results of the per-node throughput and the end-to-end delay for different network sizes. Using these results, we were able to propose a number of per-node throughput scaling laws. Our simulation results show that the per-node throughput with multiple channels for the fully connected, the line, and the grid ad hoc network topologies increases by 90% to 253%, by 47%, and by 139% to 163%, respectively, for networks with 16 to 64 nodes, as compared with that of a single channel.
In this paper, we present Queue Length based Fair Queueing (QLFQ), a scheme to approximate fair bandwidth allocation without per-flow state. We have evaluated QLFQ together with CSFQ and RFQ with several different con...
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In this paper, we present Queue Length based Fair Queueing (QLFQ), a scheme to approximate fair bandwidth allocation without per flow state. Edge routers divide each flow into a set of layers using a linear encoding s...
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In this paper, we present Queue Length based Fair Queueing (QLFQ), a scheme to approximate fair bandwidth allocation without per flow state. Edge routers divide each flow into a set of layers using a linear encoding scheme and insert an appropriate label into each packet header. Core routers maintain a dropping threshold at each router; packets with a label greater than the threshold are dropped. In order to determine the dropping threshold, we only need to know queue occupancy information and do few comparison operations in core routers (so we call our scheme Queue Length based Fair Queueing (QLFQ)). We have evaluated QLFQ together with CSFQ and RFQ with several different configurations and traffic sources. The simulation results show that QLFQ is able to achieve approximately fair bandwidth sharing in all of these scenarios. The performance of QLFQ is comparable to that of CSFQ, and it performs much better than RFQ.
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