文摘
We introduce a new notion, lossy key encapsulation mechanism (lossy KEM), which enhances the notion of key encapsulation mechanism with lossiness, and can be more efficient than lossy trapdoor functions. We show that lossy KEM can be constructed from lossy trapdoor functions, lossy trapdoor relations, and entropic projective hashing. Using lossy KEM as a building block, several previous constructions of lossy encryption and deterministic public key encryption can be generalized and improved in efficiency.