There are no standardised interconnection procedures for interconnecting different IoT networks for roaming as far as we know. Currently, roaming infrastructures are siloed to their respective IoT technologies or applications. Roaming mechanisms used in Cellular, Wi-Fi cannot be applied directly in IoT for various reasons. For example, a human is not behind the IoT End device for decision making, multi-stakeholders involving multi-layer interconnection agreements and heterogeneity in IoT identification, technologies and applications. The focus of IoTRoam is to have an operational roaming set up that can be easily deployed today, scale seamlessly, integrated to existing IoT infrastructures with minimum adaptions, requires minimum initial configuration and work on a global basis. Based on the technical community’s feedback, we started focusing on a specific IoT connectivity technology called LoRaWAN and extend the concept to other IoT technologies. As a Proof-of-Concept, we have designed, implemented and tested a roaming platform based on LoRaWAN. For implementing the Proof-of-Concept, we used well-established infrastructures such as PKI and the DNS. The IoTRoam experience has helped us update the LoRaWAN backend specifications and propose solutions for operational issues. We also evaluate whether the proposed mechanisms satisfy the constrained IoT requirements. We are in touch with several academic institutions and the LoRa Alliance community, who have expressed interest in the federated platform’s interoperability testing.