Cross-Sender Bit-Mixing Coding

TL;DR

This paper introduces cross-sender bit-mixing coding (BMC), a novel approach that enables high network utilization without complex scheduling, by controlling overlaps through coding, achieving near-optimal efficiency across all network topologies.

Contribution

The paper presents BMC, a scheduling-free coding scheme that guarantees constant medium utilization rate in all network topologies with low complexity.

Findings

Achieves  medium utilization rate in all topologies.

Low polynomial complexity for encoding and decoding.

Eliminates the need for complex scheduling in wireless networks.

Abstract

Scheduling to avoid packet collisions is a long-standing challenge in networking, and has become even trickier in wireless networks with multiple senders and multiple receivers. In fact, researchers have proved that even {\em perfect} scheduling can only achieve $\mathbf{R} = O(\frac{1}{\ln N})$. Here $N$ is the number of nodes in the network, and $\mathbf{R}$ is the {\em medium utilization rate}. Ideally, one would hope to achieve $\mathbf{R} = \Theta(1)$, while avoiding all the complexities in scheduling. To this end, this paper proposes {\em cross-sender bit-mixing coding} ({\em BMC}), which does not rely on scheduling. Instead, users transmit simultaneously on suitably-chosen slots, and the amount of overlap in different user's slots is controlled via coding. We prove that in all possible network topologies, using BMC enables us to achieve $\mathbf{R}=\Theta(1)$. We also prove that the space and time complexities of BMC encoding/decoding are all low-order polynomials.