IoRT ROS 2 Applications: Evaluating Zenoh and VPN for Robotic Networking in the Edge-Cloud Continuum

Applications in the Internet of Robotic Things (IoRT) add an additional layer of complexity over traditional robotics, namely, networking and communication with the edge and the cloud. The field of cloud robotics has already revolutionized robotic systems, among others, by offloading computationally intensive tasks to the cloud. However, existing approaches are not necessarily suitable for real-time communication and distributed computing, and are not natively supported by widespread robotic middlewares such as ROS 2. Traditional Virtual Private Networks (VPNs) have been widely adopted for secure communication, but often introduce complexity in the setup and latency that can hinder real-time performance. Zenoh, an emerging data-centric networking framework, offers an alternative with low-latency, efficient data dissemination optimized for edge-to-cloud scenarios. Zenoh also integrates seamlessly with ROS 2, enabling lower overhead communication. This paper presents a comparative study of VPN and Zenoh in edge-cloud robotics, focusing mainly on communication latency, data throughput, and fault tolerance within a real-world robotic use case. Through experimental analysis, we highlight the strengths and limitations of both approaches and provide insight into their suitability for distributed robotic applications. The findings contribute to understanding the trade-offs between security, latency, and scalability in networking solutions for the IoRT.