Capillary multi-path routing with FEC for real-time multimedia

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Applying forward error correction (FEC) in off-line streaming with large buffering time dramatically improves the quality and performance of communications under challenging network conditions. However real-time streaming puts hard restrictions on the buffer size and therefore does not allow FEC to compensate for long link failures on single path routes. However, multi-path routing, orthogonal to buffering, can make FEC effective also for real-time streaming. For this purpose we introduce a capillary routing algorithm offering layer by layer a wide range of multi-path routing topologies starting from a simple multi-path solution and evolving toward more reliable and secure schemes. The friendliness of a particular multi-path routing scheme is rated by a measure called Redundancy Overall Requirement (ROR), which is proportional to the total amount of the FEC codes required for combating the individual failures of all links in the multi-path route. A dozen of capillary routing layers, built on several hundreds of network samples obtained from a random walk wireless Mobile Ad-Hoc Network (MANET), are rated with ROR. We show that the overall amount of FEC codes decreases substantially as the spreading of the routing grows.