Caching and distributing of network packets among devices has been accepted by the research community as a cost-effective method of transferring especially audio-video data among mobile users. Another newly established technology, blockchain, has been successfully applied to decentralized financial systems like Bitcoin. The research on caching and distributing methods has not focused on the security aspect so far. In this article, we present an effective scheme to provide security and integrity of network packets in caching and distribution systems by employing the blockchain technology. Unlike the existing blockchain applications, the proposed protocol requires a lightweight consensus algorithm. Our scheme also allows peers in the network to make correctly addressed inquiries as the packets’ locations are kept in the blocks which are available to any peer in the network. Considering that cryptographic primitives alone are not adequate to prevent malicious network packets among the peers, the proposed blockchain application presents an invaluable tool to prevent malicious packets from leaking into the system and to address which peers own the desired packets. We demonstrate the efficiency of the proposed method by implementing it for Android OS devices and conduct real-time testing on different settings.

By introducing high randomness with reduced computational cost, physical layer (PHY) key generation is one of the candidate tools that can be used for the security of the Internet of Things applications. Nonidentical secret keys are one of the main problems of the physical layer (PHY) key generation schemes. In order to address this problem, key verification schemes, which are based on information reconciliation, are used in this article. In the current key verification techniques, the legitimate nodes reveal some information related to their secret keys to eliminate nonidentical bits. In this article, by jointly using PHY key generation with an embedded key, we propose a hybrid key generation and key verification scheme, where the revealed information during the key verification process is negligible, and the verified keys are identical. Numerical results and software-defined radio-based tests show that the proposed verification scheme achieves the requirements of the Industrial Internet of Things systems.