FHE: The Future Path of Privacy Computing

Fully Homomorphic Encryption ( FHE ) is an advanced cryptographic technique that enables direct computation on encrypted data. It makes it possible to process sensitive data while protecting privacy, and has broad application prospects in fields such as finance, healthcare, and cloud computing.

The basic principle of FHE is to encrypt plaintext using polynomials and perform homomorphic operations on ciphertext. To overcome the problem of noise accumulation, FHE employs techniques such as key switching, modulus switching, and bootstrapping. Currently, mainstream FHE schemes include BGV, BFV, CKKS, and others.

Although FHE can theoretically support arbitrary computations, its enormous computational overhead is the main barrier to its practical application. Compared to ordinary computation, FHE is about 500 million times less efficient. To address this, institutions such as DARPA are conducting specialized research to enhance FHE performance through means such as custom hardware accelerators.

In the blockchain domain, FHE can be used to protect transaction privacy and enable scenarios such as private voting. Some projects like Zama and Fhenix are exploring the combination of FHE with blockchain. However, the current FHE technology is still in its early stages and is some way from large-scale commercial use.

The emergence of future FHE chips will be an important milestone. With advancements in technology and deeper exploration of applications, FHE is expected to play a significant role in fields that have high requirements for privacy protection, such as defense, finance, and healthcare, unlocking the potential of private data.