From the Holy Grail of Cryptography to Practical Applications: Progress and Prospects of Fully Homomorphic Encryption Technology

Fully Homomorphic Encryption ( FHE ), as an important breakthrough in the field of Cryptography, is gradually moving from theory to practice. FHE allows for arbitrary computations and operations on encrypted data, bringing new possibilities for privacy computing.

Overview of FHE Technology

The core feature of FHE is that it allows computation on ciphertexts, and these operations can be directly mapped to the plaintext. Compared to partial homomorphic encryption, FHE supports an unlimited number of computation operations.

Currently, Microsoft's SEAL and Zama's TFHE are two major open-source FHE libraries. The basic process of using FHE includes: generating keys, encrypting data, performing homomorphic computations, and decrypting results. The secure management of the decryption key is crucial.

FHE Practice on Blockchain

The fhEVM launched by Zama is a solution that supports the use of Fully Homomorphic Encryption (FHE) in Ethereum smart contracts. It provides FHE operation support through precompiled contracts and has designed a dedicated memory area to store FHE ciphertext.

The Fhenix project further combines fhEVM with Rollup technology, proposing the FHE-Rollups Layer2 solution. It adopts the Optimistic Rollups mechanism and introduces a relay module that allows other blockchains to access FHE functionality.

The Application Prospects of FHE

FHE technology has broad application space in fields such as full-chain games, DeFi, and AI:

• Protect player privacy and asset security in the game
• Prevent MEV attacks in DeFi, protect sensitive data
• Protecting personal privacy data in AI training

The Initial Form of the FHE Ecosystem

Apart from Zama and Fhenix, projects like Sunscreen, Mind Network, and PADO Labs are also actively exploring the applications of FHE. Non-profit organizations such as FHE.org are also promoting relevant research and education.

With the maturity of technology and the improvement of the ecosystem, FHE is expected to bring new development opportunities for blockchain and Web3. We hold an optimistic attitude towards the prospects of FHE and look forward to its greater role in the future.