Notary schemes allows high-efficiency communication using side chain technology and achieve cross-chain asset transfer. Suppose the blockchain has the block header and body, and the header has information such as Merkle root. The body of chain b can include the header of chain a, and both can use the same consensus verification method to establish communication. In a cross-chain asset transfer, the notary scheme can use a trusted distributed node to declare to a chain that a change has occurred in another chain, or to validate a statement.
Currently, there are several mainstream ways of cross-chaining: notary schemes, sidechains/relays, hash-locking, and distributed private key control. Ambr's cross-chain technology excels in interoperability, security, and robustness, and is suitable for cross-chain switching, cross-chain asset transfer, cross-chain oracles, cross-chain asset collateral, and multi-currency; nearly all cross-chain usage scenarios through the usage of smart contracts.