Towards Fast and Scalable Private Inference
Jianqiao Mo Karthik Garimella Negar Neda Austin Ebel Brandon Reagen
Privacy and security have rapidly emerged as first order design constraints.
Users now demand more protection over who can see their data (confidentiality)
as well as how it is used (control). Here, existing cryptographic techniques
for security fall short: they secure data when stored or communicated but must
decrypt it for computation. Fortunately, a new paradigm of computing exists,
which we refer to as privacy-preserving computation (PPC). Emerging PPC
technologies can be leveraged for secure outsourced computation or to enable
two parties to compute without revealing either users' secret data. Despite
their phenomenal potential to revolutionize user protection in the digital age,
the realization has been limited due to exorbitant computational,
communication, and storage overheads.
  This paper reviews recent efforts on addressing various PPC overheads using
private inference (PI) in neural network as a motivating application. First,
the problem and various technologies, including homomorphic encryption (HE),
secret sharing (SS), garbled circuits (GCs), and oblivious transfer (OT), are
introduced. Next, a characterization of their overheads when used to implement
PI is covered. The characterization motivates the need for both GCs and HE
accelerators. Then two solutions are presented: HAAC for accelerating GCs and
RPU for accelerating HE. To conclude, results and effects are shown with a
discussion on what future work is needed to overcome the remaining overheads of
PI.