Publikationen

Autor	Schneider, Thomas; Yalame, Hossein; Yonli, Michael
Datum	2023
Art	Conference Proceedings
Abstrakt	This paper presents Griffin, an extension of the mixed-scheme single-key homomorphic encryption framework Pegasus (Lu et al., IEEE S&P’21) to a Multi-Key Homomorphic Encryption (MKHE) scheme with applications to secure computation. MKHE is a generalized notion of Homomorphic Encryption (HE) that allows for operations on ciphertexts encrypted under different keys. However, an efficient approach to evaluate both polynomial and non-polynomial functions on encrypted data in MKHE has not yet been developed, hindering the deployment of HE to real-life applications. Griffin addresses this challenge by introducing a method for transforming between MKHE ciphertexts of different schemes. The practicality of Griffin is demonstrated through benchmarks with multiple applications, including the sorting of sixty four 45-bit fixed point numbers with a precision of 7 bits in 21 minutes, and evaluating arbitrary functions with a one-time setup communication of 1.4 GB per party and 2.34 MB per ciphertext. Moreover, Griffin could compute the maximum of two numbers in 3.2 seconds, a 2× improvement over existing MKHE approaches that rely on a single scheme.
Konferenz	20th International Conference on Security and Cryptography (SECRYPT'23)
ISBN	978-989-758-666-8
ISSN	2184-7711
In	Proceedings of the 20th International Conference on Security and Cryptography - SECRYPT, p.147-158
Publisher	SciTePress
Url	https://tubiblio.ulb.tu-darmstadt.de/id/eprint/138035