Fault-Tolerant Real-Time Streaming with FEC thanks to Capillary Multi-Path Routing

Erasure resilient FEC codes in off-line packetized streaming rely on time diversity. This requires unrestricted buffering time at the receiver. In real-time streaming the playback buffering time must be very short. Path diversity is an orthogonal strategy. However, the large number of long paths increases the number of underlying links and consecutively the overall link failure rate. This may increase the overall requirement in redundant FEC packets for combating the link failures. We introduce the Redundancy Overall Requirement (ROR) metric, a routing coefficient specifying the total number of FEC packets required for compensation of all underlying link failures. We present a capillary routing algorithm for constructing layer by layer steadily diversifying multi-path routing patterns. By measuring the ROR coefficients of a dozen of routing layers on hundreds of network samples, we show that the number of required FEC packets decreases substantially when the path diversity is increased by the capillary routing construction algorithm

Fault-Tolerant Streaming with FEC through Capillary Multi-Path Routing

Abstract – Erasure resilient FEC codes in off-line packetized streaming rely on time diversity, which in its turn relies on unrestricted buffering time at the receiver. In real-time streaming the playback buffering time must be very short. Path diversity is an orthogonal strategy, but its drawback is that large number of long paths increases the number of underlying links and consecutively the overall link failure rate. It may result in increase of the overall requirement in redundant FEC packets combating the link failures. We introduce Redundancy Overall Requirement (ROR), a routing coefficient of the total number of FEC packets required for compensation of all underlying link failures. We present capillary routing algorithm constructing layer by layer steadily diversifying multi-path routing patterns. By measuring ROR coefficients of a dozen of routing layers on hundreds of network samples, we show that the number of required FEC packets decreases substantially when the path diversity is achieved by capillary routing algorithm. I

Rating of Routing by Redundancy Overall Need

Thanks to the large buffering time of off-line streaming applications, erasure resilient Forward Error Correction (FEC) codes can improve the reliability of communication particularly well. However real-time streaming puts hard restrictions on the buffer size making FEC inefficient for combating long link failures on single path routes. Path diversity is orthogonal to buffering and permits real-time streaming to also benefit from application of FEC. We introduce a capillary routing algorithm offering layer by layer a wide range of multi-path routing topologies starting from a simple solution and evolving toward reliable routing patterns with highly developed path diversity. The friendliness of a multi-path routing pattern is rated by the overall amount of FEC redundancy required for combating the non-simultaneous failures of all links of the communication footprint. We rated the friendliness of a dozen of capillary routing layers, built on several hundreds of network samples obtained from a random walk Mobile Ad-Hoc Network (MANET). The overall requirement in redundant FEC codes decreases substantially as the spreading of the routing grows

Multipath Routing in Wireless Sensor Networks: Survey and Research Challenges

A wireless sensor network is a large collection of sensor nodes with limited power supply and constrained computational capability. Due to the restricted communication range and high density of sensor nodes, packet forwarding in sensor networks is usually performed through multi-hop data transmission. Therefore, routing in wireless sensor networks has been considered an important field of research over the past decade. Nowadays, multipath routing approach is widely used in wireless sensor networks to improve network performance through efficient utilization of available network resources. Accordingly, the main aim of this survey is to present the concept of the multipath routing approach and its fundamental challenges, as well as the basic motivations for utilizing this technique in wireless sensor networks. In addition, we present a comprehensive taxonomy on the existing multipath routing protocols, which are especially designed for wireless sensor networks. We highlight the primary motivation behind the development of each protocol category and explain the operation of different protocols in detail, with emphasis on their advantages and disadvantages. Furthermore, this paper compares and summarizes the state-of-the-art multipath routing techniques from the network application point of view. Finally, we identify open issues for further research in the development of multipath routing protocols for wireless sensor networks