Hybrid Encrypted Mempools

The article proposes a hybrid encrypted mempool design for Ethereum, in which users encrypt transactions that a threshold committee decrypts, with the user able to open them if the committee is offline. It argues that existing private submission channels such as MEV Protect, MEV Blocker and BuilderNet do not protect all users, citing that someone gets sandwiched about every 30 seconds according to Hildobby's dashboard. The authors say the design combines Anders' Sealed Transactions with threshold encryption, since the committee deters users from selectively opening transactions for MEV. They also propose hybrid encryption with on-chain symmetric ciphertexts and sampled data availability.