Enhanced Unicast Rateless Code Based Communications over Long Fat Networks

Rateless code based communications for unicast applications require the decoder to indicate successful decoding of a batch of input packets before the encoder moves to a new batch. This will cause significant overhead when the number of input packets is restricted or when considering long distance, high capacity links. This is mainly due to the fact by the time the acknowledgement packet is received at the encoder, a large number of redundant encoded packets are injected into the communication link. This study proposes a practical solution to address the issue by introducing a two- level acknowledgment scheme and by dynamically accounting for the on-the-fly packets. The solution is implemented in an end-to-end rateless-code based scenario where the experimental results confirm the feasibility of the solution and notable throughput improvement gains when using this scheme.