Ph. B. Burtyka - Post-graduate Student at Computer Science Center of South Federal University. E-mail: fburtyka@sfedu.ru
A.V. Trepacheva - Post-graduate Student at Computer Science Center of South Federal University. E-mail: atrepacheva@sfedu.ru

A simple fully homomorphic encryption scheme is presented. Operation of the circuit is based on well-known efficient algorithms for constructing isomorphic extensions of finite fields. Security of the scheme is based on the inability to build an appropriate extension of a finite field without knowledge of the polynomial, as well as the high complexity of the frequency analysis for a large data with unknown statistic. The possibility of encryption on the data computed in polynomial cryptosystem "Polly Cracker" and other homomorphic cryptosystems is considered. Evaluated polynomial encryption gives the ability to hide from the server not only customer data, but also the algorithm performed. It sould be noted that previous authors working on homomorphic encryption considered the statement of problem, where the server hides from client their secret algorithm (or function) while the client hides from server the secret data. In our statement the client has both secret algorithm (function) and data that need to be protected from the server performed computing. This statement of the problem can be considered as particular case of algorithms obfuscation.

 

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