Due to the explosive growth of the Internet, stream services are becoming more popular. The large media servers supporting thousands of concurrent media streams have to satisfy us with both good throughout and high av...
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ISBN:
(纸本)8955191197
Due to the explosive growth of the Internet, stream services are becoming more popular. The large media servers supporting thousands of concurrent media streams have to satisfy us with both good throughout and high availability. Although they are reciprocal from the viewpoint of system performance, the stream service continuity, as well as throughput, should be considered in clustered media servers. This is because media stream services should be continuously available to the clients even on the event of system failure. In this paper, we introduce service availability as the gauge of service degree on media servers, and present the basic scheme for guaranteeing continuous stream service. To do this, we propose LSS(Log Stream Status) and RRD(Ready Resource for instant Delivery) mechanisms. They are classified according to the status management method of stream service and the resumption method of closed service. Although these mechanisms require additional overhead, we found that they can be applied to clustered media servers with minimum overhead. Additionally, we concluded that they can provide higher quality of service availability on traditional clustered media servers.
As Grid Computing is becoming a reality, there is a need for managing and monitoring the available resources worldwide, as well as the need for conveying these resources to the everyday user. This paper describes a re...
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Grid computing presents a new trend to distributed computation and Internet applications, which can construct a virtual single image of heterogeneous resources, provide uniform application interface and integrate wide...
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Summary form only given. Mobile ad hoc networks (MANET) and the Internet exhibit differences in their network architecture. These differences concern the various sorts of assumptions imposed not only on the structure ...
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Summary form only given. Mobile ad hoc networks (MANET) and the Internet exhibit differences in their network architecture. These differences concern the various sorts of assumptions imposed not only on the structure and topology of the underlying networks, but also on communication patterns of mobile nodes in both networks. Integrating MANET and the Internet into a hybrid network is a challenging problem due to these differences. We propose a three-layer approach that uses both mobile IP and dynamic destination-sequenced distance vector (DSDV) to integrate these two types of networks into a hybrid environment, in order to provide MANET nodes with Internet connectivity and access to the Internet resources. Our approach is based on the use of mobile gateways as an interface between MANET and the Internet. These mobile gateways can use mobile IP when they communicate with the Internet and DSDV when they interact with MANET. We also show the results of several simulation experiments that were conducted to study the integrated environment.
Multicasting is a one-to-many process by wbich a node can send the same packet to a subset of nodes, called multicast group, which have already registered to the same multicast group address. The goal of this paper is...
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Multicasting is a one-to-many process by wbich a node can send the same packet to a subset of nodes, called multicast group, which have already registered to the same multicast group address. The goal of this paper is to propose a multicast algorithm for mobile ad hoc networks using location information, where a multicast group is definro with respect to a specific network space area, called millticost domain. A mohile ad hoc network (MANET) is a set of nodes that agrero upon fonning a spontaneous, temporar y network so that they can communicate over wireless Iinks despite the lack of any centraIized administration and any fonn or infrastructure. The proposed algorithm benefits from the location-oriented service offered by a glohal positioning system (GPS), which provides MANET nodes (or nodes for short) with their location information when needed. Moreover, the protocol makes use of the Vorono; diagram properties in order to multicast a packet in a selective manner towards its target multicast dOmain, where ouly a small subset of nodes is involved in the forwarding process. These nodes, called authorized forwarders, are identified from the *** Voronoi graph that a multicast source node or an authorized forwarder constructs based on the location infonnation of its neighborhood as well as the target multicast domain. The analysis bas shown that fhe protocol helps minimize the transmission overhead, which would be caused during the forwarding of a multicast packet, while guaranteeing convergence and correctness. Compared to other existing location-based multicast protocols, the proposed one yields more reduction of transmission overhead and perfonns correctly even with particular MANET topologies. Keywords - Multicasting, mobile ad hoc networks, locationbased service, Voronoi diagmms, global positioning system.
The quality of service (QoS) of wireless Internet access that could be provided to multihop wireless networks, so-called mobile ad hoc networks (MANETs), is highly dependent on the quality of the design of the interme...
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The quality of service (QoS) of wireless Internet access that could be provided to multihop wireless networks, so-called mobile ad hoc networks (MANETs), is highly dependent on the quality of the design of the intermediate facility that will integrate MANET and the Internet. This facility is equipped with a hybrid mechanism being able to fulfill the working requirements of MANET and the Internet so that it can connect to either one of these orthogonal network architectures. The architecture that we propose in order to provide MANET nodes with Internet access utilizes fixed gateways (or access points) and exploits the mobility capability of additional mobile ones. Since Internet access to MANET nodes is provided through mobile gateways, the quality of such service depends on the selection procedure used by MANET nodes to choose the most convenient mobile gateways and register with. In this paper, we suggest to use a hybrid criterion based on the weighted sum of the Euclidean distance between MANET nodes and mobile gateways, and the load of mobile gateways, defined as the number of MANET nodes currently registered with them. Moreover, the sum of the weights is normalized to one, where each weight measures the level of interest of the corresponding criterion in the hybrid one. Simulation results show that the hybrid criterion has an impact on the quality of wireless Internet access service depending on the level of interest assigned to each of the Euclidean distance and load criteria in the weighted sum.
A mobile ad hoc network (MANET) is a set of mobile nodes that agreed upon forming a temporary, spontaneous network in spite of the lack of any infrastructure or centralized administration. MANET topology changes frequ...
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A mobile ad hoc network (MANET) is a set of mobile nodes that agreed upon forming a temporary, spontaneous network in spite of the lack of any infrastructure or centralized administration. MANET topology changes frequently and arbitrarily due to node mobility. Therefore, an efficient routing protocol is required to cope with the dynamic change of MANET topology, which requires discovering and maintaining new routes, in this paper we propose a route discovery protocol based on location information, which could be provided to MANET nodes by a Global Positioning System (GPS). Our route discovery protocol utilizes the essential features of Voronoi diagrams in order to reduce the search space of routes by allowing only a small subset of MANET nodes, called authorized forwarders, to forward a route request. This results in a restrictive, selective route discovery protocol, which significantly reduces the routing overhead compared to other location-based routing protocol, such as LAR.
Due to the explosive growth of the Internet, stream services are becoming more popular. The large media servers supporting thousands of concurrent media streams have to satisfy us with both good throughout and high av...
详细信息
ISBN:
(纸本)8955191197
Due to the explosive growth of the Internet, stream services are becoming more popular. The large media servers supporting thousands of concurrent media streams have to satisfy us with both good throughout and high availability. Although they are reciprocal from the viewpoint of system performance, the stream service continuity, as well as throughput, should be considered in clustered media servers. This is because media stream services should be continuously available to the clients even on the event of system failure. In this paper, we introduce service availability as the gauge of service degree on media servers, and present the basic scheme for guaranteeing continuous stream service. To do this, we propose LSS(Log Stream Status) and RRD(Ready Resource for instant Delivery) mechanisms. They are classified according to the status management method of stream service and the resumption method of closed service. Although these mechanisms require additional overhead, we found that they can be applied to clustered media servers with minimum overhead. Additionally, we concluded that they can provide higher quality of service availability on traditional clustered media servers.
This paper describes the UIcluster software tool, which partitions expressed sequence tag (EST) sequences and other genetic sequences into "clusters" based on sequence similarity. Ideally, each cluster will ...
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