摘要 : This study discusses the problem of key distribution protocol in IoT systems especially smart grids for two modes of communication: Unicast and multicast. In the present paper, we suggested two protocols for key distribution for b... 展开 This study discusses the problem of key distribution protocol in IoT systems especially smart grids for two modes of communication: Unicast and multicast. In the present paper, we suggested two protocols for key distribution for both unicast and multicast communication. The proposed schemes are based on symmetric key encryption with cryptographic primitives: Hashes and nonces. In addition, the multicast key distribution protocol is based on a logical key hierarchy to reduce communication and computation overheads in case of any member change. The proposed solutions are compared to other protocols based on communication and computation overheads, and the ability to resist well-known attacks. The comparison shows that the proposed protocols have the lowest overheads while resisting known attacks. To ensure the correctness and security of the proposed protocol, it is analyzed using a logical tool (BAN logic). The analysis illustrates that the proposed protocols are free from bugs or redundancies. 收起