V2X Content Distribution Based on Batched Network Coding with Distributed Scheduling

TL;DR

This paper introduces a joint I2V and V2V content distribution scheme using batched network coding and distributed scheduling to efficiently share data among vehicles with minimal delay and overhead.

Contribution

It proposes a novel combined infrastructure-to-vehicle and vehicle-to-vehicle scheme with a utility-based distributed scheduling algorithm and optimized BATS coding for vehicular content sharing.

Findings

Significantly reduces transmission delay compared to existing protocols.

Effectively handles lossy channels and short connection times in vehicular networks.

Achieves efficient content sharing in realistic traffic scenarios.

Abstract

Content distribution is an application in intelligent transportation system to assist vehicles in acquiring information such as digital maps and entertainment materials. In this paper, we consider content distribution from a single roadside infrastructure unit to a group of vehicles passing by it. To combat the short connection time and the lossy channel quality, the downloaded contents need to be further shared among vehicles after the initial broadcasting phase. To this end, we propose a joint infrastructure-to-vehicle (I2V) and vehicle-to-vehicle (V2V) communication scheme based on batched sparse (BATS) coding to minimize the traffic overhead and reduce the total transmission delay. In the I2V phase, the roadside unit (RSU) encodes the original large-size file into a number of batches in a rateless manner, each containing a fixed number of coded packets, and sequentially broadcasts them during the I2V connection time. In the V2V phase, vehicles perform the network coded cooperative sharing by re-encoding the received packets. We propose a utility-based distributed algorithm to efficiently schedule the V2V cooperative transmissions, hence reducing the transmission delay. A closed-form expression for the expected rank distribution of the proposed content distribution scheme is derived, which is used to design the optimal BATS code. The performance of the proposed content distribution scheme is evaluated by extensive simulations that consider multi-lane road and realistic vehicular traffic settings, and shown to significantly outperform the existing content distribution protocols.