Decoding window strategies reduce delay and complexity in network coding
Evict Early, Decode Efficiently: Lightweight Decoding Strategies for Low-Delay Sliding Window RLNC
Networking and Internet Architecture
Summary
Reliable communication over networks often needs fast and efficient error correction. The paper looks at how to manage the 'decoding window'—the set of packets being processed at once—in a type of network coding that helps send data quickly and reliably. The authors found ways to remove old packets safely and deliver data faster without making decoding harder. Their new methods reduce the time it takes to get data in order and make the computer work less during decoding.
What this means in practice
- •For network engineers: Use improved decoding window policies to reduce latency and computational load in real-time communication protocols.
- •For satellite communication teams: Enhance reliable data delivery in dynamic non-terrestrial networks by applying lightweight decoding strategies.
Authors
Foteini Karetsi, Evangelos Papapetrou
Abstract
Random Linear Network Coding (RLNC), and in particular Sliding Window RLNC (SW-RLNC), is a promising approach for reliable, low-latency communication in dynamic environments such as 6G and non-terrestrial networks. While prior work has largely focused on encoder-side parameter tuning, such as the code rate and coding window size, decoder-side design remains comparatively underexplored despite its direct impact on end-to-end performance. This paper addresses decoding window management, namely the policies governing window-boundary updates, removal of obsolete packets, and delivery of recovered packets to upper layers, and shows that these policies critically shape the trade-off between computational complexity and decoding performance, particularly in-order delivery delay. We derive sufficient conditions under which packets can be safely removed from the decoding window without compromising decodability or violating in-order delivery guarantees, and, building on these conditions, propose two lightweight decoding window management schemes. Through extensive simulation-based evaluation across a range of channel conditions and code rates, we show that both schemes preserve decoding efficiency while substantially reducing decoding complexity, and that one additionally achieves a marked reduction in in-order delivery delay. These results establish decoding window management as a key design dimension for practical SW-RLNC systems.