Packet loss

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

Packet network and method for congestion avoidance in packet networks

Abstract: Packet transfer is controlled by using an acceleration rate of packet transfers or by using a packet transfer rate acceleration ratio to predict that congestion will occur at a prescribed time in the future. Congestion avoidance in packet integrated networks is thereby achieved in a network having both variable rate terminal nodes and fixed rate terminal nodes. A future packet transfer rate is predicted in a congestion prediction circuit on the basis of a pre-established upper limit for the packet transfer acceleration or acceleration ratio. When it is predicted that the packet transfer rate will exceed a permissible value, a congestion prediction signal is output or a rate increase request indication is deleted. The invention prevents packets from being discarded in the packet network, allows buffer memory capacity of nodes in the network to be decreased, and avoids the generation of new packets when signal congestion is predicted.

A bandwidth allocation/sharing/extension protocol for multimedia over IEEE 802.11 ad hoc wireless LANs

Abstract: We propose a novel bandwidth allocation/sharing/extension (DBASE) protocol to support both asynchronous traffic and multimedia traffic with the characteristics of variable bit rate (VBR) and constant bit rate (CBR) over IEEE 802.11 ad hoc wireless local area networks. The overall quality of service (QoS) will be guaranteed by DBASE. The designed DBASE protocol will reserve bandwidth for real-time stations based on a fair and efficient allocation. Besides, the proposed DBASE is still compliant with the IEEE 802.11 standard. The performance of DBASE is evaluated by analysis and simulations. Simulations show that the DBASE is able to provide almost 90% channel utilization and low packet loss due to delay expiry for real-time multimedia services.

Method for constructing adaptive packet lengths in a congested network

Abstract: In a network, the efficiency of data transfer is improved. The network includes packets of data (100, 120). The invention begins by preserving an original packet (100). A larger packet (140) is then constructed by combining two packets (100, 120). Either the original packet (100) or the larger packet (140) is transmitted over the network. The original packet (100) is transmitted if the media/port (52) becomes available for transmission before the larger packet (140) is constructed, and the larger packet (140) is transmitted if the constructing of the larger packet (140) is completed before the media (52) becomes available. In a network with cells, a packet is constructed by combining cells. This packet is built until the media becomes available for transmission. The size and composition of this packet is independent of an original packet's size and composition.

Self-tuned congestion control for multiprocessor networks

Abstract: One-track performance in tightly-coupled multiprocessors typically, degrades rapidly beyond network saturation. Consequently, designers must keep a network below its saturation point by reducing the load on the network. Congestion control via source throttling-a common technique to reduce the network load-presents new packets from entering the network in the presence of congestion. Unfortunately, prior schemes to implement source throttling either lack vital global information about the network to make the correct decision (whether to throttle or not) or depend on specific network parameters, network topology or communication pattern. This paper presents a global-knowledge-based, self-tuned, congestion control technique that prevents saturation at high loads across different network configurations and commutation pattern. Our design is composed of two key components. First, we use global information about a network to obtain a timely estimate of network congestion. We compare this estimate to a threshold value to determine when to throttle packet injection. The second component is a self-tuning mechanism that automatically determines appropriate threshold values based on throughput feedback. A combination of these two techniques provides high performance under heavy load does not penalize performance under light load, and gracefully adapts to changes in communication patterns.

Packet Loss Characterization in WiFi-Based Long Distance Networks

Abstract: Despite the increasing number of WiFi-based Long Distance (WiLD) network deployments, there is a lack of understanding of how WiLD networks perform in practice. In this paper, we perform a systematic study to investigate the commonly cited sources of packet loss induced by the wireless channel and by the 802.11 MAC protocol. The channel induced losses that we study are external WiFi, non-WiFi and multipath interference. The protocol induced losses that we study are protocol timeouts and the breakdown of CSMA over WiLD links. Our results are based on measurements performed on two real-world WiLD deployments and a wireless channel emulator. The two deployments allow us to compare measurements across rural and urban settings. The channel emulator allows us to study each source of packet loss in isolation in a controlled environment. Based on our experiments we observe that the presence of external WiFi interference leads to significant amount of packet loss in WiLD links. In addition to identifying the sources of packet loss, we analyze the loss variability across time. We also explore the solution space and propose a range of MAC and network layer adaptation algorithms to mitigate the channel and protocol induced losses. The key lessons from this study were also used in the design of a TDMA based MAC protocol for high performance long distance multihop wireless networks [12].