[Paper Review] Mobility Based Routing Protocol with MAC Collision Improvement in Vehicular Ad Hoc Networks

Zhihao Ding, Pinyi Ren+1 more|arXiv (Cornell University)|Jan 19, 2018

Vehicular Ad Hoc Networks (VANETs)16 references3 citations

TL;DR

This paper proposes a mobility-aware routing protocol for Vehicular Ad Hoc Networks (VANETs) that integrates vehicle mobility status and MAC layer contention information to improve routing decisions. By leveraging real-time mobility and channel access behavior, the protocol reduces MAC layer collisions and outperforms traditional GPSR in terms of packet delivery ratio and end-to-end delay under high mobility conditions.

ABSTRACT

Intelligent transportation system attracts a great deal of research attention because it helps enhance traffic safety, improve driving experiences, and transportation efficiency. Vehicular Ad Hoc Network (VANET) supports wireless connections among vehicles and offers information exchange, thus significantly facilitating intelligent transportation systems. Since the vehicles move fast and often change lanes unpredictably, the network topology evolves rapidly in a random fashion, which imposes diverse challenges in routing protocol design over VANET. When it comes to the 5G era, the fulfilment of ultra low end-to-end delay and ultra high reliability becomes more crucial than ever. In this paper, we propose a novel routing protocol that incorporates mobility status and MAC layer channel contention information. The proposed routing protocol determines next hop by applying mobility information and MAC contention information which differs from existing greedy perimeter stateless routing (GPSR) protocol. Simulation results of the proposed routing protocol show its performance superiority over the existing approach.

Motivation & Objective

• To address the challenge of rapid topology changes and high mobility in VANETs.
• To reduce MAC layer collisions caused by unpredictable vehicle movements and dense vehicular traffic.
• To improve routing performance in terms of delivery ratio and end-to-end delay for 5G-enabled intelligent transportation systems.
• To integrate mobility status and MAC contention feedback into routing decision-making for better path selection.

Proposed method

• The protocol uses real-time vehicle speed and direction to classify mobility states and predict link stability.
• It incorporates MAC layer backoff counter information to estimate channel contention levels and avoid congested links.
• Next-hop selection is determined by a composite metric combining mobility predictability and MAC contention awareness.
• The routing algorithm dynamically adjusts forwarding decisions based on both mobility trends and current channel access behavior.
• The approach extends the GPSR framework by adding mobility and MAC layer feedback to the forwarding decision process.
• Simulations are conducted using a realistic vehicular mobility model to evaluate performance under high-speed and high-density conditions.

Experimental results

Research questions

• RQ1 How can mobility state information be effectively used to improve routing stability in high-speed VANETs?
• RQ2 To what extent does incorporating MAC layer contention feedback reduce channel collisions in vehicular networks?
• RQ3 Can a hybrid metric combining mobility predictability and MAC contention improve routing performance compared to conventional GPSR?
• RQ4 How does the proposed protocol perform in terms of delivery ratio and end-to-end delay under high mobility and dense traffic?

Key findings

• The proposed protocol achieves a higher packet delivery ratio compared to conventional GPSR under high-mobility scenarios.
• End-to-end delay is significantly reduced due to better selection of low-contention, stable forwarding paths.
• The integration of MAC contention feedback leads to fewer retransmissions and improved channel utilization.
• The protocol demonstrates robustness in dynamic environments with frequent topology changes and lane changes.