Reducing Packet Loss in Real-Time Wireless Multicast Video Streams with Forward Error Correction

Author: Simen Fonnes

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Average packet loss without and with FEC

Wireless multicast suffers from severe packet loss due to interference and
lack of link layer retransmission. In this work, we investigate wether the
most recent Forward Error Correction (FEC) draft is suitable for realtime wireless multicast live streaming, with emphasis on three main points:
packet reduction effectivity, and latency and overhead impact. We design
and perform an experiment in which we simulate wireless packet loss in
multicast streams with a Gilbert model pattern of ≈ 16% random packet
loss. We check all FEC configurations (L and D values) within several
constraints: maximum 500 milliseconds repair window (latency impact),
66.67% overhead, and a maximum L value of 20. For all these L and D
values we stream the tractor sample three times, to avoid possible outliers
in the data. We show that packet loss reduction in the most recent FEC
draft is effective, at most reducing from ≈ 16% down to ≈ 1.02%. We
also show that low latency streaming can be conducted, but it requires a
minimum of 160 milliseconds additional latency for our stream file. The
overhead for such low latency can be as high as 66.67%.