An Efficient Chunked Network Code Based Transmission Scheme in Wireless Networks

Opportunistic routing (OR) is a promising technology to enhance the throughput of wireless networks, which can be implemented in a distributed manner using random linear network coding (RLNC). To reduce the computational cost incurred by RLNC, most previous approaches partition the input packets into disjoint small chunks, apply RLNC within each chunk, and guarantee the decoding reliability by a feedback mechanism. However, a feedback mechanism can incur much transmission overhead, reducing the network performance significantly. Recently, chunked network codes (CC) are proposed to eliminate the requirement of feedback, where a linear block code is applied on the input packets before partitioning the packets into chunks. While several classes of CC can achieve a close-tooptimal encoding/decoding performance, the whole transmission performance depends on how the chunks are transmitted in the absence of feedback, which is little investigated in OR-based wireless networks. In this paper, we propose a simple chunk transmission scheme for CC in a common OR-based wireless network, which does not require any node coordination during the transmission and keep the buffer of the relay node stable. We further optimize the performance of the transmission scheme via linear programming, and demonstrate that our scheme performs near-optimally via extensive numerical evaluations.