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Welcome to the Near <> Ethereum Bridge wiki!

Initial Bridge discussion started here: https://github.com/nearprotocol/nearcore/issues/942

What to read:

• https://medium.com/@loiluu/peacerelay-connecting-the-many-ethereum-blockchains-22605c300ad3
• https://blog.gridplus.io/efficiently-bridging-evm-blockchains-8421504e9ced

Architecture

The Bridge should be presented by smart contract based light clients and arbitrary trustless actors who wish to forward necessary data between Near and Ethereum blockchains.

The Bridge API should allow:

• Pass arbitrary data between smart contracts in different chains
• Make arbitrary calls between smart contracts in different chains

The Bridge base projects:

• Fully collaterized NEAR stable token in Ethereum network
• Fully collaterized ETH stable token in Near network
• Smart contract based Ethereum proxy-accounts for Near users
• Smart contract based Near proxy-accounts for Ethereum users

Near Bridge smart contracts

Ethereum smart contract should be Near Light Client

Described necessary data structures at this page: https://github.com/nearprotocol/bridge/wiki/Data-Structures

Helpful links:

• Precompiled contract for Ed25519 signature verification: https://github.com/ethereum/EIPs/blob/master/EIPS/eip-665.md
• Ed25519 signature verification in Solidity (1.2M+ gas each ecmul): https://github.com/javgh/ed25519-solidity

Ethereum Bridge smart contracts

Near smart contract should be Ethereum Light Client

Helpful links:

• Ethereum Light Client https://github.com/ethereum/wiki/wiki/Light-client-protocol
• Ethash validation in Near: https://github.com/nearprotocol/near-runtime-ts/blob/a2daf139b7d3ccf29730cfee76fbd27c25e9db38/apidoc/modules/_near_.md#check_ethash
• RLP Decoding in Solidity: https://github.com/hamdiallam/Solidity-RLP

ETHASH implementations:

• Wiki: https://github.com/ethereum/wiki/wiki/Ethash
• SmartPool by Kyber (Solidity): https://github.com/SmartPool/contracts/blob/develop/contracts/Ethash.sol#L460
• Parity (Rust): https://github.com/paritytech/parity-ethereum/blob/master/ethash/src/compute.rs#L164
• Waterloo Bridge by Kyber (C++): https://github.com/KyberNetwork/bridge_eos_smart_contracts/blob/master/contracts/Bridge/Bridge.cpp#L63