ArctyrEX : Accelerated Encrypted Execution of General-Purpose
  Applications
Charles Gouert Vinu Joseph Steven Dalton Cedric Augonnet Michael Garland Nektarios Georgios Tsoutsos
Fully Homomorphic Encryption (FHE) is a cryptographic method that guarantees
the privacy and security of user data during computation. FHE algorithms can
perform unlimited arithmetic computations directly on encrypted data without
decrypting it. Thus, even when processed by untrusted systems, confidential
data is never exposed. In this work, we develop new techniques for accelerated
encrypted execution and demonstrate the significant performance advantages of
our approach. Our current focus is the Fully Homomorphic Encryption over the
Torus (CGGI) scheme, which is a current state-of-the-art method for evaluating
arbitrary functions in the encrypted domain. CGGI represents a computation as a
graph of homomorphic logic gates and each individual bit of the plaintext is
transformed into a polynomial in the encrypted domain. Arithmetic on such data
becomes very expensive: operations on bits become operations on entire
polynomials. Therefore, evaluating even relatively simple nonlinear functions,
such as a sigmoid, can take thousands of seconds on a single CPU thread. Using
our novel framework for end-to-end accelerated encrypted execution called
ArctyrEX, developers with no knowledge of complex FHE libraries can simply
describe their computation as a C program that is evaluated over $40\times$
faster on an NVIDIA DGX A100 and $6\times$ faster with a single A100 relative
to a 256-threaded CPU baseline.