OTP-Based Symmetric Group Key Establishment Scheme for IoT Networks

One of the major challenges in implementing a group key establishment and management scheme to provide security solutions for group communication in the Internet of Things (IoT) is the limited resource availability of the nodes such as memory, computation, and energy. To ensure security such as confidentiality, integrity of the transmitting messages in a certain IoT group, a feasible group key establishment and management scheme is necessary which uses minimum resources but provides high scalability and strong security. In this paper, we propose a symmetric group key establishment scheme that uses the secrecy guarantee provided by One Time Pad (OTP) and performs computations like bitwise Exclusive OR (XOR) and bit shifting of randomly generated binary vectors to produce random different keys for different sessions of message transmission. We show that our scheme is lightweight to support the resource-constrained nature of IoT nodes by using only primitive operations and scalable to support the dynamic constellation of IoT network groups where nodes can join and exit frequently. We prove that our scheme is secure under a designed threat model where a similar existing scheme fails by a detailed analysis.