Lightweight protocol for trusted spontaneous communication

Abstract

We present a communication protocol with encryption, suitable for extremely weak devices, which communicate only by sending un-modulated, on/off signals (beeping). We assume severely constrained model with no coordination or synchronization between devices, and no mechanism for message reception acknowledgement. Under these assumptions, we present a way to handle the problem of transmissions interference (collisions) and providing message secrecy at the same time. In order to achieve our goals in such a limited communication channel, we use special encoding and combine encryption procedure with the communication layer of the protocol. This is different from the state-of-the-art-today, where an encrypted channel is built in the highest level of the communication protocol after assigning the radio channel to one of the sender devices. We present a real-life motivations for the proposed approach as well as rigid correctness and security analysis.