Packet loss

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

Fluid models and solutions for large-scale IP networks

Abstract: In this paper we present a scalable model of a network of Active Queue Management (AQM) routers serving a large population of TCP flows. We present efficient solution techniques that allow one to obtain the transient behavior of the average queue lengths, packet loss probabilities, and average end-to-end latencies. We model different versions of TCP as well as different versions of RED, the most popular AQM scheme currently in use. Comparisons between our models and ns simulation show our models to be quite accurate while at the same time requiring substantially less time to solve, especially when workloads and bandwidths are high.

Cross-Layer Support for Energy Efficient Routing in Wireless Sensor Networks

Abstract: The Dynamic Source Routing (DSR) algorithm computes a new route when packet loss occurs. DSR does not have an in-built mechanism to determine whether the packet loss was the result of congestion or node failure causing DSR to compute a new route. This leads to inefficient energy utilization when DSR is used in wireless sensor networks. In this work, we exploit cross-layer optimization techniques that extend DSR to improve its routing energy efficiency by minimizing the frequency of recomputed routes. Our proposed approach enables DSR to initiate a route discovery only when link failure occurs. We conducted extensive simulations to evaluate the performance of our proposed cross-layer DSR routing protocol. The simulation results obtained with our extended DSR routing protocol show that the frequency with which new routes are recomputed is 50% lower compared with the traditional DSR protocol. This improvement is attributed to the fact that, with our proposed cross-layer DSR, we distinguish between congestion and link failure conditions, and new routes are recalculated only for the latter.

Bilateral Teleoperation Over Unreliable Communication Networks

Abstract: In this brief, we propose a passivity-based framework for control of bilateral teleoperators under time-varying delays and data loss. The usual scattering formalism which guarantees passivity for any constant time delay is extended in several important ways to handle adverse network dynamics. Communication management modules (CMM) are proposed to reconstruct the scattering variables while guaranteeing passivity of the bilateral teleoperator and asymptotic stability of the master/slave velocities under time-varying delays and data losses. The results are also extended to the discrete domain, in particular to the case where communication between the master and slave robots occurs over a packet-switched network. We show that passivity can be maintained in the face of varying delay and packet loss but that it depends fundamentally on the mechanism used to handle missing packets. Our framework unifies several existing results in the continuous and discrete time domain. We develop novel algorithms for the CMM which not only preserve passivity and stability, but have been shown through experiments to improve tracking performance in a single-degree-of-freedom teleoperator system.

Optimal intra coding of blocks for robust video communication over the Internet

Abstract: Reliable transmission of compressed video in a packet lossy environment cannot be achieved without error recovery mechanisms. We describe an effective method for increasing error resilience of video transmission over packet lossy networks such as the Internet. Intra coding (without reference to a previous picture) is a well-known technique for eliminating temporal error propagation in a predictive video coding system. Randomly intra coding of blocks increases error resilience to packet loss. However, when the error concealment used by the decoder is known, intra encoding following a method that optimizes the tradeoffs between compression efficiency and error resilience is a better alternative. In this paper, we present a rate-distortion optimized mode selection method for packet lossy environments that takes into account the network conditions and the error concealment method used at the decoder. We present results for different packet loss rates and typical packet sizes of the Internet, that illustrate the advantages of the proposed method.

Performance analysis of EXP/PF and M-LWDF in downlink 3GPP LTE system

Abstract: This paper investigates the performance of exponential/proportional fair (EXP/PF) and maximum-largest weighted delay first (M-LWDF) scheduling algorithms in the third generation partnership project long term evolution (3GPP LTE) providing packet-switched multimedia services It, then, identifies a suitable packet scheduling algorithm on a basis of their performance evaluation The performance evaluation is conducted in terms of system throughput, average real time (RT) and non-real time (NRT) throughput, packet loss for RT service and fairness for NRT service A video streaming traffic is used to model the RT service, while a web-browsing traffic is modelled for NRT service Simulation results show that at lower load M-LWDF algorithm provides better performance than EXP/PF while as the load increases the EXP/PF gives better performance