Making IoT services accountable: a solution based on Blockchain and Physically Unclonable Functions

Nowadays, an important issue in the IoT landscape consists of enabling the dynamic instauration of interactions among two or more objects, operating autonomously in a distributed and heterogeneous environment, which participate in the enactment of accountable cross-organization business processes. In order to achieve the above goal, a decentralized and reliable approach is needed. Here, we propose a solution based on physical unclonable function (PUF) and blockchain technologies that represent the building blocks of the devised IT infrastructure. The core of the authentication process is based on a purposely designed circuit for the PUF bitcell, implemented in a 65 nm CMOS technology. One of the most important aspects of this work is represented by the concept of accountability node, an element inspired to a blockchain 3.0 masternode. This is the key element of the proposed architecture, acting as the main interface for cooperating services and IoT objects which relieve the users/objects from the burden of having to directly interact with the blockchain.