CRICKET: A practical physical layer key agreement protocol for IoT networks

Physical Layer Key Generation (PLKG) is an attractive method for solving the key distribution problem in IoT networks. Although PLKG has a much lower complexity when compared to public key cryptography, it is not always practical in resourceconstrained networks due to a high reconciliation cost. Channel Reciprocity for KEy Transmission (CRicKET) is an ultra-lightweight key agreement method that exploits channel reciprocity for securely transmitting a key generated at one end of a single-hop network. The key disagreement rate can be arbitrarily chosen without increasing the computational complexity. Analytical results allow design optimisation and derive the entropy requirement for perfect secrecy. The practicality of CRicKET is successfully tested on a series of IoT boards connected to a wireless network.