FHE Bridge

What is FHE Bridge 🌉

FHE Bridge is a cross-chain communication bridge developed in collaboration with Chainlink, designed to securely transmit data across different blockchains. The core technologies underpinning FHE Bridge are the Cross-Chain Interoperability Protocol (CCIP) and the Stealth Address Protocol (SAP).

Stealth Address Protocol (SAP) ⫘⫘⫘

The Stealth Address (SA) prevents the public association of a blockchain transaction's output with a recipient's wallet address, effectively concealing the actual destination address of the transaction. As italik highlighted the practical and privacy-preserving implementation of SA in the application layer of programmable blockchains such as Ethereum, we propose a SA protocol with Fully Homomorphic Encryption (FHE) to prevent quantum computing attacks based on Learning with Error (LWE) security assumption.

While the original proposal of SA builds on the dual-key, our approach , FHE-DKSAP, can help the receiver outsource the computation of checking the entire chain for stealth addresses containing assets without revealing his view key, and prevent quantum computing attacks based on the lattice cryptographic construction that relies on far simpler mathematics than elliptic curve isogenies.