Improved Public Key Cryptosystems Secure against Chosen Ciphertext Attacks
نویسنده
چکیده
This note describes an improvement to the rst two of the three public key cryptosystems proposed by Zheng and Seberry, which are provably secure against chosen ciphertext attacks. The improvement removes a shortcoming with the original cryptosystems, which occurs when they are used for both con dentiality and sender authentication purposes.
منابع مشابه
Public-key Cryptosystems Provably Secure against Chosen Ciphertext Attacks
We show how to construct a public-key cryptosystem (as originally deened by Diie and Hellman) secure against chosen ciphertext attacks, given a public-key cryptosystem secure against passive eavesdropping and a non-interactive zero-knowledge proof system in the shared string model. No such secure cryptosystems were known before.
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