Information and communication technologies (ICT) support the digital evolution of energy networks, enabling automated and smart operations. Internet of Things (IoT) devices allow automated remote measurements and data collection improving anomaly detection, predictive maintenance, and operational efficiency. When IoT devices communicate with each other they shall be authenticated within the network. Traditional authentication methods rely on certificates issued by a centralized Certification Authority (CA), that may be affected by a single point of failure and may be computationally heavy for resource constrained IoT devices.

The system “Decentralized PKI for IoT Systems” enables Blockchain-based authentication of the public keys of IoT devices. In addition, through the NSL-BC (Needham-Schroeder-Lowe Blockchain) protocol, it allows the generation of symmetric keys between two devices registered in the system. In the first prototype the devices, once authenticated through the system, use MQTT (Message Queuing Telemetry Transport) protocol to communicate with each other securely using the publish/subscribe paradigm.

In this deliverable, after analyzing the differences between the functions offered by MQTT and XMPP protocols, there are collected the activities carried out and the considerations made in performing the migration of “Decentralized PKI for IoT systems” from MQTT to XMPP. All the changes made to the system components, the edge node and the IoT client were detailed. During the integration process, code was developed to validate the processes defined through a functioning testbed that connects two devices of the system and allows the exchange of messages between them in a secure way.

Furthermore, a process for the management and automatic renewal of the keys used in the communication has been presented and implemented. The behavior of the system components has been fully automated and human interaction is no longer required. Finally, the two versions of the system were compared with each other.

The integration of the XMPP protocol in place of MQTT allows the system to be used in energy application contexts in which the XMPP protocol is already used or in which secure E2E (point-to-point) communications are desired.

The Report is available on the Italian site