An Efficient Identity-based Broadcast Signcryption Scheme

Broadcast signcryption, which enables the broadcaster to simultaneously encrypt and sign the content meant for a specific set of users in a single logical step, provides the most efficient solution to this dual problem of confidentiality and authentication. Recently, several identity-based broadcast signcryption (IBBSC) schemes have been proposed. However, we find almost all IBBSC schemes that have been proposed until now do not satisfy register secrecy and forward secrecy. Following this, we propose a new IBBSC scheme and formally prove its security under the random oracle model for broadcast signcryption (IND-CCA2 and EUF-CMA) While we propose a secure IBBSC scheme, we do not compromise the performance. The proposed scheme only requires two pairing operations for end user devices with limited computing capability.