Lossless data transfer over communication networks has traditionally been achieved by means of ARQ protocols. However, the last ten years have seen an increasing interest in using erasure-correcting codes as an alternative, with the goal of reducing latency, feedback overhead, etc. Since these two approaches possess advantages as well as drawbacks, several hybrid ARQ schemes have also been proposed as good compromise solutions, in order to attain the “best of both worlds”. Extending this principle, this paper develops new classes of hybrid ARQ protocols for erasure channels that allow for flexible trade-offs between two important cost metrics, viz., the computational complexity of coding , and the amount of feedback needed. Our hybrid schemes make use of Tornado codes – a class of low-complexity capacity-achieving erasure codes – whose coding structure is well-suited for feedback-based communications. These schemes demonstrate significant cost reductions versus coding-only and feedback-only approaches over a wide region of interest. Moreover, these schemes are easily tuned to achieve different operating points on a trade-off curve. Finally, the proposed schemes showcase novel means of interweaving coding and feedback.

中文翻译：

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基于 Tornado 码的混合 ARQ 协议用于数据包擦除通道

通信网络上的无损数据传输传统上是通过 ARQ 协议实现的。然而，在过去十年中，人们越来越关注使用纠删码作为替代方案，目的是减少延迟、反馈开销等。由于这两种方法各有优缺点，几种混合 ARQ 方案也被提议作为良好的折衷解决方案，以实现“两全其美”。扩展这一原则，本文为擦除信道开发了新类别的混合 ARQ 协议，允许在两个重要的成本指标之间进行灵活的权衡，即编码的计算复杂度，以及 需要的反馈量。我们的混合方案利用 Tornado 码——一类低复杂度的容量实现纠删码——其编码结构非常适合基于反馈的通信。这些方案与仅编码和仅反馈方法相比，在广泛的兴趣区域内显着降低了成本。此外，这些方案很容易调整以在权衡曲线上实现不同的工作点。最后，所提出的方案展示了交织编码和反馈的新方法。