Packet loss

About: Packet loss is a research topic. Over the lifetime, 21235 publications have been published within this topic receiving 302453 citations.

Sampled-Data Consensus of Linear Multi-agent Systems With Packet Losses

Abstract: In this paper, the consensus problem is studied for a class of multi-agent systems with sampled data and packet losses, where random and deterministic packet losses are considered, respectively. For random packet losses, a Bernoulli-distributed white sequence is used to describe packet dropouts among agents in a stochastic way. For deterministic packet losses, a switched system with stable and unstable subsystems is employed to model packet dropouts in a deterministic way. The purpose of this paper is to derive consensus criteria, such that linear multi-agent systems with sampled-data and packet losses can reach consensus. By means of the Lyapunov function approach and the decomposition method, the design problem of a distributed controller is solved in terms of convex optimization. The interplay among the allowable bound of the sampling interval, the probability of random packet losses, and the rate of deterministic packet losses are explicitly derived to characterize consensus conditions. The obtained criteria are closely related to the maximum eigenvalue of the Laplacian matrix versus the second minimum eigenvalue of the Laplacian matrix, which reveals the intrinsic effect of communication topologies on consensus performance. Finally, simulations are given to show the effectiveness of the proposed results.

Flow control method for quality streaming of audio/video/media over packet networks

Abstract: A method and apparatus for client-side detection of network congestion in a best-effort packet network comprising streaming media traffic is disclosed. Said method and apparatus provide for quality streaming media services in a congested network with constrained bandwidth over the last-mile link. A client media buffer detects at least one level of congestion and signals a server to enact at least one error mechanism. Preferred error mechanisms include packet retransmissions, stream prioritization, stream acceleration, changes in media compression rate, and changes in media resolution. Said method and apparatus allow distributed management of network congestion for networks comprising multiple clients and carrying significant streaming media traffic.

Methods and systems for forward error correction based loss recovery for interactive video transmission

Abstract: Real-time interactive video transmission in the current Internet has mediocre quality because of high packet loss rates. Loss of packets belonging to a video frame is evident not only in the reduced quality of that frame but also in the propagation of that distortion to successive frames. This error propagation problem is inherent in any motion-based video codec because of the interdependence of encoded video frames. Since packet losses in the best-effort Internet environment cannot be prevented, minimizing the impact of these packet losses to the final video quality is important. A new forward error correction (FEC) technique effectively alleviates error propagation in the transmission of interactive video. The technique is based on a recently developed error recovery scheme called Recovery from Error Spread using Continuous Updates (RESCU). RESCU allows transport level recovery techniques previously known to be infeasible for interactive video transmission applications to be successfully used in such applications. The FEC technique can be very useful when the feedback channel from the receiver is highly limited, or transmission delay is high. Both simulation and Internet experiments indicate that the FEC technique effectively alleviates the error spread problem and is able to sustain much better video quality than H.261 or other conventional FEC schemes under various packet loss rates.

Forward error correction strategies for media streaming over wireless networks

Abstract: The success of next-generation mobile communication systems depends on the ability of service providers to engineer new added-value multimedia-rich services, which impose stringent constraints on the underlying delivery/transport architecture. The reliability of real-time services is essential for the viability of any such service offering. The sporadic packet loss typical of wireless channels can be addressed using appropriate techniques such as the widely used packet-level forward error correction. In designing channel-aware media streaming applications, two interrelated and challenging issues should be tackled: accuracy of characterizing channel fluctuations and effectiveness of application-level adaptation. The first challenge requires thorough insight into channel fluctuations and their manifestations at the application level, while the second concerns the way those fluctuations are interpreted and dealt with by adaptive mechanisms such as FEC. In this article we review the major issues that arise when designing a reliable media streaming system for wireless networks.

Packet loss effects on MPEG video sent over the public Internet

Abstract: 1. BSTWCT This paper presents results from a study of stieaming h~EG compressed video over the pubHc Inteme& using the RTP and UDP tianspoti protocok. TmTofie minute video etips were h~EG coded at rates of 384 Kbps and 1 l~ps. The resultant coded streams were transmitted at their respective data ra$esbe~een four sites in the United States and Europa hIeasurements w’ere taken be~een sites during aHhours of the day for seveml weeks at a time to generate a clear pictire of the time varying nature of Internet errors. The paper concentrates on ne~ork loss/error characteristics that specifica~y affect the quali~ of the received ~~EG compressed stieams. Due to the nature of h~EG data streams, losses in certain pati of the data stieam are more disturbing when viewed than losses in other parts of the data stieam. For instance, since N~EG video is inter-fmme coded, artifacts due to netiork loss/emors, can persist for many frames. Thus, a meaningful measure of received video qua~ty requires a more thorough analysis of netiork errors than average error rates. Our results include patterns of packet lossover tim~ conditional packet 10SS