LinkLab 2.0: A Multi-tenant Programmable IoT Testbed for Experimentation with Edge-Cloud Integration.

In this paper, we present LinkLab 2.0, a completely programmable and controllable IoT testbed with the support of edge devices and cloud infrastructures. To be more specific, LinkLab 2.0 leverages a tiered architecture for the programmable devices and the management system to achieve scalability. To better support the integrated experiment among IoT, edge and cloud, LinkLab 2.0 provides one-site programming support and leverages the customizable offloading with serverless functions. Moreover, LinkLab 2.0 proposes a device-involved multi-tenancy approach to ensure responsiveness for concurrent requests. Furthermore, targeting 24/7 availability for experimenters, LinkLab 2.0 leverages proactive and reactive anomaly detection to improve the reliability of the testbed. Finally, we describe the supported research experiments and the outreach usage by external users. We also report lessons learned from the four-year operation. LinkLab 2.0 has supported experiments for 2,100+ users. The accumulated usage time across all the devices exceeds 17,300 hours.