Unclonable encryption, introduced by Broadbent and Lord (TQC’20), is an encryption scheme with the following attractive feature: given a ciphertext, adversary cannot create two ciphertexts both of which decrypt to same message as original ciphertext.We revisit this notion show following: 1. Reusability: The constructions proposed have disadvantage that they either guarantee one-time security (t...

Encryption in database systems is an important topic for research, as secure and efficient algorithms are needed that provide the ability to query over encrypted database and allow optimized encryption and decryption of data. Clearly, there is a compromise between the degree of security provided by encryption and the efficient querying of the database, because the operations of encryption and d...

Searchable asymmetric encryption (SAE) can also be called Public Key Encryption with Keyword Search (PEKS), which allows us to search the keyword on the data of having been encrypted. The essence of Asymmetric searchable encryption is that users exchange the data of encryption, one party sends a ciphertext with key encryption, and the other party with another key receives the ciphertext. Encryp...

We propose a security notion named as weak adaptive chosen ciphertext security(INDWCCA) for hybrid encryption schemes. Although it is weaker than adaptive chosen ciphertext security(INDCCA), a IND-WCCA secure hybrid encryption scheme can be used in any situations that a IND-CCA secure hybrid encryption scheme used in. We show that IND-WCCA secure hybrid encryption scheme can be constructed from...