Lack of communication made it hard to exchange and transfer the value of assets between chains, leaving their economies isolated. It has been a common practice to mint assets such as USD and BTC in a chain through fixed value in a centralized method using the FIAT Gateway method, and utilize them in a chain. This method is based on the trust of the centralized subject. There are questions about uncertainty due to lack of information and the security of the assets. To resolve these issues, many protocols have emerged for communication between unconnected blockchains through decentralization of the communication.