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54
Multi-path routing for multiple description video over wireless ad hoc networks
- in Proc. IEEE INFOCOM 2005
, 2005
"... Abstract—We study the problem of multipath routing for double description (DD) video in wireless ad hoc networks. We follow an application-centric cross-layer approach and formulate an optimal routing problem that minimizes the application layer video distor-tion. We show that the optimization probl ..."
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Cited by 42 (13 self)
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Abstract—We study the problem of multipath routing for double description (DD) video in wireless ad hoc networks. We follow an application-centric cross-layer approach and formulate an optimal routing problem that minimizes the application layer video distor-tion. We show that the optimization problem has a highly complex objective function and an exact analytic solution is not obtainable. However, we find that a meta-heuristic approach such as genetic algorithms (GAs) is eminently effective in addressing this type of complex cross-layer optimization problems. We provide a detailed solution procedure for the GA-based approach. Simulation results demonstrate the superior performance of the GA-based approach versus several other approaches. Our efforts in this work provide an important methodology for addressing complex cross-layer op-timization problems, particularly those involved in the application and network layers. Index Terms—Ad hoc networks, cross-layer design, metaheuris-tics, multipath routing, multiple description video, optimization. I.
MRTP: A multi-flow real-time transport protocol
, 2004
"... Abstract—Real-time multimedia transport has stringent quality of service requirements, which are generally not supported by current network architectures. In emerging mobile ad hoc networks, frequent topology changes and link failures cause severe packet losses, which degrade the quality of received ..."
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Cited by 33 (6 self)
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Abstract—Real-time multimedia transport has stringent quality of service requirements, which are generally not supported by current network architectures. In emerging mobile ad hoc networks, frequent topology changes and link failures cause severe packet losses, which degrade the quality of received media. However, in such mesh networks, there usually exist multiple paths between any source and destination nodes. Such path diversity has been demonstrated to be effective in combating congestion and link failures for improved media quality. In this paper, we present a new protocol to facilitate multipath transport of real-time multimedia data. The proposed protocol, the multiflow real-time transport protocol (MRTP), provides a convenient vehicle for real-time applications to partition and transmit data using multiple flows. We demonstrate through analysis that data partitioning, which is an essential function of MRTP, can effectively reduce the short-range dependence of multimedia data, thus improving its queueing performance in underlying networks. Furthermore, we show that a few flows are sufficient for MRTP to exploit most of the benefits of multipath transport. Finally, we present a comprehensive simulation study on the performance of MRTP under a mobile ad hoc network. We show that with one additional path, MRTP outperformed single-flow RTP by a significant margin. Index Terms—Ad hoc networks, multipath transport, real-time transport protocol, traffic partitioning, video communications. I.
Multiple description video multicast in wireless ad hoc networks,” ACM/Kluwer Mobile Netw
- Appl. J
, 2006
"... Abstract. Multiple description (MD) coding is a new video coding technique that is uniquely suitable for video transport over wireless ad hoc networks. In this paper, we consider the problem of how to support video multicast with MD video in ad hoc networks. We follow an application-centric, cross-l ..."
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Cited by 21 (9 self)
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Abstract. Multiple description (MD) coding is a new video coding technique that is uniquely suitable for video transport over wireless ad hoc networks. In this paper, we consider the problem of how to support video multicast with MD video in ad hoc networks. We follow an application-centric, cross-layer routing approach with the objective of minimizing the overall video distortion. We propose an MD video multicast scheme where multiple source trees are used. Furthermore, each video description is coded into multiple layers in order to cope with diversity in wireless link bandwidths. Based on this multicast model, we formulate the cross-layer multicast routing as a combinatorial optimization problem and propose an efficient Genetic Algorithm (GA)-based metaheuristic solution procedure. Performance comparison with existing approaches show significant gains for a wide range of network operating conditions.
Cross-layer optimized multipath routing for video communications in wireless networks
- IEEE J. Select. Areas Commun
, 2007
"... Abstract — Traditionally, routing is considered solely as a network layer problem and has been decoupled from application layer objectives. Although such an approach offers simplicity in the design of the protocol stack, it does not offer good performance for certain applications such as video. In t ..."
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Cited by 20 (6 self)
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Abstract — Traditionally, routing is considered solely as a network layer problem and has been decoupled from application layer objectives. Although such an approach offers simplicity in the design of the protocol stack, it does not offer good performance for certain applications such as video. In this paper, we explore the problem of how to perform routing with the objective of optimizing application layer performance. Specifically, we consider how to perform multipath routing for multiple description (MD) video in a multi-hop wireless network. We formulate this problem into an optimization problem with application performance metric as the objective function and routing and link layer considerations as constraints. We develop a formal branch-and-bound framework and exploit the so-called Reformulation-Linearization Technique (RLT) in the solution procedure. We show that this solution procedure is able to produce a set of routes whose objective value is within (1 − ) of the optimum. We use simulation results to substantiate the efficacy of the solution procedure and compare the performance with that under non-cross-layer approach. Index Terms — Video communications, multipath routing, mul-tiple description (MD) coding, optimization.
Realizing the benefits of user-level channel diversity
- SIGCOMM Comput. Commun. Rev
, 2005
"... Realizing the Benefits of User-Level Channel Diversity Channel or path diversity is known to improve performance in physical layer designs, channel access strategies, path switching mechanisms, etc. In this paper, we focus on "user-level " mechanisms that operate simply by distributing pac ..."
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Cited by 14 (6 self)
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Realizing the Benefits of User-Level Channel Diversity Channel or path diversity is known to improve performance in physical layer designs, channel access strategies, path switching mechanisms, etc. In this paper, we focus on "user-level " mechanisms that operate simply by distributing packet transmissions across multiple channels. We seek to understand when, why, and to what extent this can be of benefit, and equally important, whether these benefits can be realized with as little of an added cost as possible. In that context, our main contribution is not so much in identifying optimal policies for leveraging channel diversity, but in introducing the concept of channel "equivalence " and demonstrating that channel diversity yields substantial benefits mostly when channels are approximately equivalent. We build on this finding to investigate the robustness of these improvements against errors in the characterization of the available channels or changes in their characteristics. We also explore the sensitivity of the results as the number of available channels varies. The findings of the paper demonstrate that by allowing packet transmissions from multiple users to intelligently share channels, it is possible to improve overall
Interference Aware Multi-Path Selection for Video Streaming in Wireless Ad Hoc Networks
, 2008
"... In this paper, we propose a novel multi-path selection framework for video streaming over wireless ad hoc networks. We propose a heuristic interference-aware multipath routing protocol based on the estimation of concurrent packet drop probability of two paths, taking into account interference betw ..."
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Cited by 11 (0 self)
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In this paper, we propose a novel multi-path selection framework for video streaming over wireless ad hoc networks. We propose a heuristic interference-aware multipath routing protocol based on the estimation of concurrent packet drop probability of two paths, taking into account interference between links. Through both simulations and actual experiments, we show that the performance of the proposed protocol is close to that of the optimal solution, and is better than that of other heuristic protocols.
PATH SELECTION FOR MULTI-PATH STREAMING IN WIRELESS AD HOC NETWORKS
, 2006
"... In this paper, we propose a novel multi-path selection framework for streaming over wireless ad hoc networks. Our approach is to approximately estimate the concurrent packet drop probability of two paths by taking into account the interference between different links, and to select the best path pai ..."
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Cited by 9 (0 self)
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In this paper, we propose a novel multi-path selection framework for streaming over wireless ad hoc networks. Our approach is to approximately estimate the concurrent packet drop probability of two paths by taking into account the interference between different links, and to select the best path pair based on that estimation. We prove the optimal path selection problem to be NP-hard, and propose a heuristic solution, whose performance is shown to be close to that of the optimal solution, while significantly outperforming other heuristic protocols.
Improving Performance Through Channel Diversity in the Presence of Bursty Losses
- In Proceedings of ITC'19
, 2005
"... Abstract. As more applications migrate to IP networks, ensuring a consistent level of service is increasingly important. One option is for the network to offer service guarantees. Another is to leverage the path diversity that the Internet intrinsically offers. Our focus is on understanding if an wh ..."
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Cited by 8 (4 self)
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Abstract. As more applications migrate to IP networks, ensuring a consistent level of service is increasingly important. One option is for the network to offer service guarantees. Another is to leverage the path diversity that the Internet intrinsically offers. Our focus is on understanding if an when one can indeed take advantage of multiple disjoint paths to improve performance. We consider an environment where loss patterns are bursty and where coding is used to provide robustness against packet losses. We assume that only long-term loss statistics are known about each path, and we seek to identify the best strategy for sending packets over the available paths. Our contributions are two-fold. First we demonstrate that even with minimal knowledge of channel characteristics and using simple transmission policies, path diversity can help significantly improve performance. Second, we derive an efficient method for identifying optimal policies, and more importantly characterize when having access to multiple paths can be of benefit. Keywords: Channel Diversity, Cross-layer designs, Reliability and fault tolerance. 1
MobiStream: Error-Resilient Video Streaming in Wireless WANs using Virtual Channels
- Proceedings of IEEE Infocom, 2006. (A.R.: 17
, 2006
"... that exploits the perceptual value in video content and the characteristics of the link layer and physical layer channels to enable error-resilient video streaming over wireless wide-area networks (WWANs). The key building block in MobiStream is the use of link-layer based, but application-controlle ..."
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Cited by 6 (1 self)
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that exploits the perceptual value in video content and the characteristics of the link layer and physical layer channels to enable error-resilient video streaming over wireless wide-area networks (WWANs). The key building block in MobiStream is the use of link-layer based, but application-controlled, virtual channels (ViCs) abstraction. Each virtual channel offers a level of reliability and statistical loss gaurantees using ‘awareness ’ of the characteristics of link-layer and physical layer channels. Video applications can dynamically instantiate new virtual channels, control their loss behavior, and/or flexibly switch video transmission across channels. MobiStream achieves fine-grained error-resilience by partitioning video frames into number of small, independently decodable, blocks of data (called ‘slices’) and assigns priority based on its perceptual (visual) usefulness. MobiStream augments a number of other enhancements for error-resilience: multiple description coding, perceptual slice-structured coding, low-delay inter-frame and intra-frame slice interleaving, dynamic unequal error protection, and priority-based video-data scheduling to enable error-resilient video streaming over wireless wide-area links. MobiStream has been implemented and evaluated using loss distributions from tests over a commercial wide-area wireless (CDMA2000 EvDO) network. Results show that, even in stationary conditions, MobiStream, on average, improves video picture quality by at least 4 dB. We conclude that significant benefits to end-user experience can be obtained by deploying such a system. I.
