• Kamujula VishnuvardhanReddy
• P.Bhargavi

Recent surveys reveals a powerful attacker which breaks data confidentiality by acquiring cryptographic keys, by means of coercion or backdoors in cryptographic software. Once the encryption key is exposed, the only viable measure to preserve data confidentiality is to limit the attacker’s access to the cipher text. Nevertheless, if data is encrypted with existing schemes, an adversary equipped with the encryption key, can still compromise a single server and decrypt the cipher text blocks stored therein. In this paper, we study data confidentiality against an adversary which knows the encryption key and has access to a large fraction of the cipher text blocks. To this end, we propose Bastion, a novel and efficient scheme that guarantees data confidentiality even if the encryption key is leaked and the adversary has access to almost all cipher text blocks.

"SECURE COMPUTING OF CLOUD BY HOMOMORPHIC ENCRYPTION AND MULTIPARTY COMPUTATION", International Journal of Emerging Technologies and Innovative Research (www.jetir.org), ISSN:2349-5162, Vol.9, Issue 12, page no.b432-b443, December-2022, Available :http://www.jetir.org/papers/JETIR2212146.pdf

"SECURE COMPUTING OF CLOUD BY HOMOMORPHIC ENCRYPTION AND MULTIPARTY COMPUTATION", International Journal of Emerging Technologies and Innovative Research (www.jetir.org | UGC and issn Approved), ISSN:2349-5162, Vol.9, Issue 12, page no. ppb432-b443, December-2022, Available at : http://www.jetir.org/papers/JETIR2212146.pdf