The rapid development in portable computing platforms, distributed multimedia systems and wireless communication technologies has led to a significant interest in mobile multimedia and wireless networking. Video enter...
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ISBN:
(纸本)0769513212
The rapid development in portable computing platforms, distributed multimedia systems and wireless communication technologies has led to a significant interest in mobile multimedia and wireless networking. Video entertainment and multimedia Internet access over wireless networks are examples of future wireless personal communication systems. These, however, incur challenging technological issues. The synchronization of the multimedia objects among mobile clients is one of the most important of these issues. The task of synchronization in wireless multimedia systems is to eliminate variations and delays incurred during the transmission of multiple-media streams and to maintain the temporal order among the various media streams. We propose an efficient distributed multimedia synchronization algorithm for wireless and mobile multimedia systems to ensure and facilitate mobile clients' access to multimedia objects. We discuss the algorithm and provide its formal proof and correctness.
Abstract: Data Distribution Management (DDM) is a High Level Architecture/Run-time Infrastructure (HLA/RTI) service that manages the distribution of state updates and interaction information in large scale distributed...
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Abstract: Data Distribution Management (DDM) is a High Level Architecture/Run-time Infrastructure (HLA/RTI) service that manages the distribution of state updates and interaction information in large scale distributedsimulations, limits and controls the volume of data exchanged during the simulation. In this paper we focus upon the following three DDM schemes: Region-Based, Fixed and Dynamic Grid-Based techniques. In an effort to determine the most efficient model for applying the DDM service, we developed a mini-RTI Kit framework and propose a set of benchmarks to compare these DDM schemes. Using the RTI Kit, we performed extensive simulation experiments and present our analysis of the results of numerous federation executions.
Ad hoc networks are wireless, mobile networks that can be set up anywhere and anytime without the aid of any established infrastructure or centralized administration. Because of the limited range of each host's wi...
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ISBN:
(纸本)0769510922
Ad hoc networks are wireless, mobile networks that can be set up anywhere and anytime without the aid of any established infrastructure or centralized administration. Because of the limited range of each host's wireless transmission, to communicate with hosts outside its transmission range, a host needs to enlist the aid of its nearby hosts in forwarding packets to the destination. However, since there is no stationary infrastructure such as base stations, each host has to act as a router for itself. A routing protocol for ad hoc networks is executed on every host and is therefore subject to the limit of the resources at each mobile host. A good routing protocol should minimize the computing load on the host as well as the traffic overhead on the network. Therefore, a number of routing protocols have been proposed for ad hoc wireless networks. We focus upon on-demand schemes. We study and compare the performance of the following three routing protocols AODV, CBRP and DSR. A variety of workload and scenarios, as characterized by mobility, load and size of the ad hoc network were simulated. Our results indicate that despite its improvement in reducing route request packets, CBRP has a higher overhead than DSR because of its periodic hello messages while AODV's end-to-end packet delay is the shortest when compared to DSR and CBRP.
Ad hoc networks are useful for providing communication support where no fixed infrastructure exists or the deployment of a fixed infrastructure is not economically profitable, and movement of communicating parties is ...
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Ad hoc networks are useful for providing communication support where no fixed infrastructure exists or the deployment of a fixed infrastructure is not economically profitable, and movement of communicating parties is allowed. Therefore, such networks are designed to operate in widely varying environments, from military networks to low-power sensor networks and other embedded systems. Frequent topology changes caused by node mobility make routing in ad hoc wireless networks a challenging problem. In this paper, we propose an efficient ad hoc routing algorithm, which we refer to as GZRP, a hybrid protocol that makes use of the ZRP scheme and the Global Positioning System (GPS). As opposed to the ZRP original scheme, our GZRP scheme consists of propagating the routing (query) messages only to the nodes that are further away from the query source. We discuss the algorithm, its implementation, and report on the performance of GZRP scheme, and compare it to the ZRP routing protocol using an extensive simulation experiment. Our results indicate clearly that GZRP outperforms ZRP by reducing significantly the number of route query messages, and thereby increases the efficiency of the network load. Furthermore, we show that careful GPS screening angle is an important factor in the success of the GZRP ad hoc routing protocol.
The advances in mobile computing and distributed multimedia systems allow mobile hosts (clients) to access wireless multimedia systems anywhere at anytime, but not without creating a new set of issues and trade-offs. ...
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The advances in mobile computing and distributed multimedia systems allow mobile hosts (clients) to access wireless multimedia systems anywhere at anytime, but not without creating a new set of issues and trade-offs. To the best of our knowledge, there has been very little research done to deal with the synchronization problem in wireless and mobile multimedia systems. We propose an efficient distributed synchronization algorithm for wireless and mobile multimedia systems to ensure and facilitate mobile clients' access of multimedia objects. We describe our synchronization scheme, which we refer to as MoSync, its implementation, and report on the performance results that we have obtained using a discrete event simulation testbed we have developed. Our results indicate clearly that our synchronization scheme is a viable approach to a wireless multimedia environment.
A mobile ad-hoc network (Manet) is a system of wireless mobile nodes dynamically self-organizing in arbitrary and temporary network topologies. People and vehicles can thus be internetworked in areas without a pre-exi...
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ISBN:
(纸本)0780370015
A mobile ad-hoc network (Manet) is a system of wireless mobile nodes dynamically self-organizing in arbitrary and temporary network topologies. People and vehicles can thus be internetworked in areas without a pre-existing communication infrastructure, or when the use of such infrastructure requires wireless extension. Therefore, such networks are designed to operate in widely varying environments, from military networks to low-power sensor networks and other embedded systems. Frequent topology changes caused by node mobility make routing in ad hoc wireless networks a challenging problem. We focus upon routing protocols for ad hoc networks. We study and compare the performance of several routing protocols. A variety of workload and scenarios using a variety of mobility, load and size of the ad hoc network were simulated.
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