PREFHE, PREFHE-AES and PREFHE-SGX: Secure Multiparty Computation Protocols from Fully Homomorphic Encryption and Proxy ReEncryption With AES and Intel SGX

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Yakupoğlu Karaağaç C.

EAI SecureComm 2022 - 18th EAI International Conference on Security and Privacy in Communication Networks, Kansas, United States Of America, 17 - 19 October 2022, pp.738-756

  • Publication Type: Conference Paper / Full Text
  • City: Kansas
  • Country: United States Of America
  • Page Numbers: pp.738-756
  • Abdullah Gül University Affiliated: No


We build our secure multiparty computation (MPC) proto-

cols on top of the fully homomorphic encryption (FHE) scheme, BFVrns,

and augment it with Proxy Re-Encryption (PRE). We offer three dis-

tinct secure MPC protocols that make use of the Advanced Encryption

Standard (AES) and Intel Software Guardian Extension (SGX). The

PREFHE protocol is based on FHE and PRE that offers a reasonable

computational time of milliseconds or seconds, depending on the func-

tion computed jointly on the parties’ encrypted data. It offers 4 rounds

and a communication cost that only depends on the parties’ cipher-

text size. PREFHE-AES employs AES-128 encryption, which reduces

the cost of communication to bits rather than kilobytes or megabytes

while maintaining the same number of rounds as PREFHE. PREFHE-

SGX is another novel approach that reduces the number of rounds from

4 to 3 by utilizing only one untrusted server. Additionally, it delivers a

reasonable level of performance that is applicable to real-world use cases.

We pioneer the use of SGX and FHE in secure MPC protocols, resulting

in reduced number of rounds. In the protocols, after parties send their

encrypted data to the server, they are not required to be online that

improves practicality in the protocols. Additionally, the parties are not

required to collaborate on any computations during the encryption and

decryption phases that makes our protocols more efficient than other

proposed protocols.