Packet loss

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

Time-Sensitive Networking: An Introduction

Abstract: Ethernet is cheap and ubiquitous. As such, people want to use it to carry all sorts of traffic for which it was not originally intended. A popular current application area is the transport of multiple flows of data, each having different timing requirements. Such applications exist in professional audio, industrial and automotive networks, among others. This article briefly traces the history of the features of IEEE 802 Bridging intended to address those needs, and then describes recent advances in time-sensitive networking in more detail. As well as completed standards, some current projects are described. Areas for future standardization are identified. Encoding the priority of packets in the header allows high-priority packets to be scheduled for transmission ahead of lower-priority packets, providing a better quality of service for urgent traffic. Time-sensitive flows have varying requirements for maximum latency and latency variation. Audio-video bridging provides guaranteed quality of service in terms of those parameters, for booked traffic in a bridged network comprising only compliant bridges. Some types of flow (particularly in industrial networks) are very sensitive to packet loss. Time-sensitive networking can provide bounded latency and zero packet loss due to congestion. The most stringent guarantees and most efficient use of network resources is provided by cyclic queuing and forwarding, which combines time synchronization, transmission scheduling and per-stream filtering and policing to provide just-in-time delivery of time-sensitive streams. This requires careful planning and centralized control. Less stringent use cases allow use of distributed control techniques.

Load Frequency Control with Communication Topology Changes in Smart Grid

Abstract: In this paper, the quality of service of communication infrastructure implemented in multiarea power system for load frequency control application is assessed in smart grid environment. In this study, network induced effects time delay, packet loss, bandwidth, quantization, and change in communication topology (CT) has been addressed to examine the system performance in closed loop. Uncertainty in time delay is approximated using deterministic and stochastic models. The network is modeled considering different network configurations, i.e., change in CT. The modeled communication network guarantees control relevant properties, i.e., stability. The decentralized controller and linear matrix inequality-based linear quadratic regulator is implemented to reduce the dynamic performance (mean square error of states variables) of power system as CT changes. Simulation results suggest that the proposed scheme of networked control is superior with respect to other design methods available in the literature, and thus robust to communication imperfections.

System and method for framing and protecting variable-lenght packet streams

Abstract: A method and a system for framing variable-length packets in a data communications system are disclosed. The successive variable-length packets carrying users' data, are formed in a stream of chained packets comprising a header. Two CRC's are computed. One over the data and another one over the header however, including also the data CRC of the immediate previous packet, thus chaining successive packets in a steam of such packets. The invention also assumes that encryption is performed independently over header and corresponding CRC's and, on the other hand, over the data of current packet. The invention allows to better adapt the transportation of multi-media users' data in packets of variable-lengths while securing transport by chaining successive packets, thus preventing that accidental or malicious deletion and insertion of packets occur and remain undetected. Also, the invention permits that intermediate transport nodes, owning keys to decrypt headers, may perform packet add/drop multiplexing without requiring that users' data need to be decrypted on their way to their final destination.

Communications system having distributed control and real-time bandwidth management

Abstract: A communications system and method utilizes peer-to-peer architecture to provide "quality" real-time communications in a non-guaranteed, packet-based network. Quality real-time communications in a non-guaranteed, packet-based network is achieved by (i) minimizing packet loss, (ii) minimizing latency, and (iii) minimizing the artifacts caused by packet loss. The system distributes control of functionality to the peer communication devices, thereby eliminating the need for a central processor to establish peer-to-peer communications. Each of the peer communication devices has the capability to respond to variations in network loading to provide quality real-time communications.

Loss tolerant transmission control protocol

Abstract: Provided are apparatuses and methods for transmitting or receiving data packets in a data block in a communication network with a transport protocol. In one example, a loss tolerant TCP protocol is used in which a maximum segment size (MSS) may be adapted to a minimum granularity of a congestion window. Also, proactive forward error correction (FEC) packets may be added to a window of the data block. The number of proactive FEC packets may be determined, for example, based on an estimate erasure rate. In addition, reactive FEC packets may be added to the data block. Also, a receiver may receive data packets in a data block and process a selective acknowledgment (SACK) responsive to the data packets received.