The recent advancements in miniaturized smart data collecting devices pushed the need of securing communications between people and devices. Traditional approaches based on key exchange protocol can’t be performed by resource-constrained embedded devices, and a novel approach, based on a robust decentralization of the eXtended Triple Diffie-Hellman (X3DH) protocol, has been proposed, namely the BlockChain-Based X3DH (BCB-X3DH) protocol. This work progresses the analysis further to fit a generic Smart City scenario with Edge and IoT nodes, performing intensive analysis on Raspberry Pi 3 model B+ and Raspberry Pi 4 to validate that the new protocol is not only resistant from well-known distributed attacks but can also be executed by miniaturized hardware with benefits in terms of resources, energy consumption and battery life-cycle.