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

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