Interoperable chains open up a world where moving assets from one platform to another, or payment- versus-payment and payment-versus-delivery schemes, or accessing information from one chain inside another (eg.“identity chains” and payment systems may be a plausible link) becomes easy and even
implementable by third parties without any additional effort required from the operators of the base blockchain protocols.
So far the notion of chain interoperability has seen much theory and little practice, primarily because a live example of successful chain interoperability requires not one, but two, already existing, stable and sufficiently powerful blockchains to build off of, but this is slowly starting to change.
Across the chain technology is mainly to solve different main chain (such as: ‘ HLC ‘ and ‘ BTC ‘) problem of data exchange between the most direct cross chain technology application is “DEX:distributed exchange”, No third party participation will purse ‘ BTC ‘ into ‘ HLC ‘,Complete wallet-to-wallet transactions.
Currently, Qitmeer has supported P2SH script contracts and cross-chain functions through hash-locking.