Ballot secrecy and ballot independence: definitions and relations
نویسندگان
چکیده
We study ballot independence for election schemes. First, we formally define ballot independence as a cryptographic game and prove that ballot secrecy implies ballot independence. Secondly, we introduce a notion of controlled malleability and prove that it is sufficient for ballot independence. We also prove that non-malleable ballots are sufficient for ballot independence. Thirdly, we prove that ballot independence is sufficient for ballot secrecy in a special case. Our results show that ballot independence is necessary in election schemes satisfying ballot secrecy. Furthermore, our sufficient conditions enable simpler proofs of ballot secrecy.
منابع مشابه
Secrecy and independence for election schemes
We study ballot secrecy and ballot independence for election schemes. First, we propose a definition of ballot secrecy as an indistinguishability game in the computational model of cryptography. Our definition builds upon and strengthens earlier definitions to ensure that ballot secrecy is preserved in the presence of an adversary that controls the bulletin board and communication channel. Seco...
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