was going through the Cosmos IBC implementation on Ethereum and found something pretty interesting. Ethereum is verifying Cosmos consensus using zero knowledge proofs through SP1. instead of running the entire CometBFT light client verification inside an Ethereum contract, they run the verification off-chain in a Rust program, generate a ZK proof, and verify that proof on Ethereum. and this is already running on mainnet. I found their June upgrade records where they migrated the Ethereum light clients to SP1 v6.1 and successfully relayed Cosmos Hub packets using the new verifier. also checked their gas benchmarks. receiving an existing ERC20 through IBC takes around 551k gas in their Foundry tests, but when they batch 50 packets together, the average drops to around 175k gas per packet. that's roughly 68% less gas per packet. but there's another side to this. the system still depends on the Cosmos validator set, correct SP1 verification programs and keys, and a governance setup that can upgrade or recover the light clients. so ZK verification doesn't automatically mean there are zero trust assumptions. I think this is the interesting part of where interoperability is heading. we're moving complex consensus verification off-chain and using cryptographic proofs to make it practical on other blockchains. source: https://t.co/Y6IL0hSehd