[Paper Review] An SDN hybrid architecture for vehicular networks: Application to Intelligent Transport System

Soufian Toufga, Philippe Owezarski+2 more|arXiv (Cornell University)|Dec 14, 2017

Vehicular Ad Hoc Networks (VANETs)17 citations

TL;DR

This paper proposes a novel SDN-based hybrid architecture integrating DSRC and cellular networks to enhance vehicular connectivity for Intelligent Transport Systems (ITS). By enabling centralized, programmable control over multi-homed vehicles, the architecture supports low-latency, reliable services through dynamic, context-aware routing and load balancing, leveraging environmental data like traffic density and vehicle trajectories via cloud integration.

ABSTRACT

Vehicular networks are one of the cornerstone of an Intelligent Transportation System (ITS). They are expected to provide ubiquitous network connectivity to moving vehicles while supporting various ITS services, some with very stringent requirements in terms of latency and reliability. Two vehicular networking technologies are envisioned to jointly support the full range of ITS services : DSRC (Dedicated Short Range Communication) for direct vehicle to vehicle/Road Side Units (RSU) communications and cellular technologies. To the best of our knowledge, approaches from the literature usually divide ITS services on each of these networks according to their requirements and one single network is in charge of supporting the each service. Those that consider both network technologies to offer multi-path routing, load balancing or path splitting for a better quality of experience of ITS services assume obviously separately controlled networks. Under the umbrella of SDN (Software Defined Networking), we propose in this paper a hybrid network architecture that enables the joint control of the networks providing connectivity to multi-homed vehicles and, also, explore the opportunities brought by such an architecture. We show through some use cases, that in addition to the flexibility and fine-grained programmability brought by SDN, it opens the way towards the development of effective network control algorithms that are the key towards the successful support of ITS services and especially those with stringent QoS. We also show how these algorithms could also benefit from information related to the environment or context in which vehicles evolve (traffic density, planned trajectory, ..), which could be easily collected by data providers and made available via the cloud.

Motivation & Objective

• To address the challenge of supporting diverse ITS services with stringent QoS requirements in vehicular networks.
• To enable joint control of DSRC and cellular networks for multi-homed vehicles, overcoming limitations of separate network management.
• To explore the benefits of SDN's programmability and centralized intelligence in enhancing network performance for ITS applications.
• To integrate real-time environmental context (e.g., traffic density, vehicle trajectories) into network control decisions via cloud-based data sharing.
• To develop effective network control algorithms that dynamically adapt to changing network and traffic conditions.

Proposed method

• Designing a hybrid SDN architecture that unifies control of DSRC and cellular networks using a centralized controller.
• Implementing multi-path routing and load balancing across DSRC and cellular links for improved reliability and reduced latency.
• Integrating context-aware data (e.g., vehicle speed, trajectory, traffic density) from external data providers into the SDN controller via the cloud.
• Utilizing SDN's programmability to enable fine-grained, real-time control over routing and resource allocation decisions.
• Defining a control plane that coordinates between the two network types based on QoS requirements and current network state.
• Leveraging the cloud to aggregate and disseminate contextual information to the controller for intelligent decision-making.

Experimental results

Research questions

• RQ1 How can DSRC and cellular networks be jointly controlled to optimize QoS for diverse ITS services?
• RQ2 What are the benefits of using SDN to unify control across heterogeneous vehicular networks?
• RQ3 How can contextual information (e.g., traffic density, vehicle trajectory) improve network control decisions in vehicular environments?
• RQ4 Can dynamic, context-aware routing algorithms enhance reliability and reduce latency in multi-homed vehicular networks?
• RQ5 What architectural components are required to enable real-time, programmable control over hybrid vehicular networks?

Key findings

• The proposed SDN hybrid architecture enables centralized, programmable control over both DSRC and cellular networks, improving adaptability and QoS management.
• Joint control of multiple access technologies allows for dynamic load balancing and multi-path routing, enhancing reliability and reducing latency.
• Incorporating contextual data (e.g., traffic density, vehicle trajectories) into the control plane enables more intelligent and responsive network decisions.
• The architecture supports effective network control algorithms tailored to stringent ITS service requirements, such as low-latency safety applications.
• The integration of cloud-based context data via the controller enables proactive and adaptive network behavior, improving overall system performance.
• The approach demonstrates the feasibility of using SDN to unify and optimize heterogeneous vehicular networks for next-generation ITS applications.