"Forward-Secure Group Encryptions from Lattices" by Jing Pan, Xiaofeng Chen et al.
Group encryption (GE) is a fundamental anonymity primitive analogue of group signature, which guarantees the decryption ability of recipients to specific ciphertexts while hiding these users within a crowd. Since its first birth by Kiayias et al., numerous constructions have been proposed, among which there is only one lattice-based scheme is post-quantum secure. However, the security of all these schemes will be damaged once an unexpected key-exposure attack occurs (which is extremely unavoidable in the real world). To solve this problem, we first consider a forward-secure group encryption pr...