Extended Notions of Security for Multicast Public Key Cryptosystems
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چکیده
In this paper we introduce two notions of security: multiuser indistinguishability and multiuser non-malleability. We believe that they encompass the correct requirements for public key encryp-tion schemes in the context of multicast communications. A precise and non-trivial analysis prove that they are equivalent to the former single-user notions, provided the number of participants is polynomial. We also introduce a new deenition for non-malleability which is simpler than those currently in use. We believe that our results are of practical signiicance: especially they support the use of PKCS#1 v.2 based on OAEP in the multicast setting.
منابع مشابه
Extended Notions of Security for Multicast Public Key Cryptosystems
In this paper we introduce two notions of security: multi-user indistinguishability and multi-user non-malleability. We believe that they encompass the correct requirements for public key encryption schemes in the context of multicast communications. A precise and non-trivial analysis proves that they are equivalent to the former single-user notions, provided the number of participants is polyn...
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