LHC-AMRSC: Lightweight and Heterogeneously Compatible Anonymous Multireceiver Signcryption Scheme for IoT Applications

Based on public-key system (PKS), the research of anonymous multi-receiver signcryption (AMRSC) is important for various applications of modern digital societies. The AMRSC schemes admit a sender (signer) to transmit an encrypted message file to multiple authorized receivers. These schemes ensure not only the authentication of the sender and the confidentiality of the encrypted message file, but also the anonymity (protecting-privacy) of these receivers. In the past, many AMRSC schemes based on different PKSs are known, but each of them is only suitable for receivers under a single PKS so that these existing AMRSC schemes cannot be applied to the environment with two heterogeneous PKSs. In this paper, we propose the first lightweight and heterogeneously compatible AMRSC scheme, termed as the LHC-AMRSC scheme, which is compatible and suitable for an IoT environment with two heterogeneous PKSs. Security theorems are formally proven to demonstrate that the proposed scheme possesses three security properties, namely, authentication, confidentiality and anonymity. As compared to the existing AMRSC schemes, the proposed scheme has the following advantages: (1) It is the first heterogeneously compatible AMRSC scheme for two heterogeneous PKSs; (2) It provides a PKS transfer method using public channels; (3) The decryption computation cost of a receiver is constant, namely, independent on the number of authorized receivers; (4) it is suited for the applications of IoT devices with low computing power; (5) it is more suitable for a large number of IoT receivers than the existing AMRSC schemes.