CSU (Cloud Storage Unit), fully known as Cloud Computer Storage, is abbreviated as CSU and developed by a team composed of top blockchain technologists from multiple countries worldwide, under the auspices of the Global Software Cloud Computing Association. CSU not only addresses the aforementioned issues but also tackles problems related to the management of encrypted digital assets, recording their value during use, and security risks. CSU employs multiple features such as encrypted digital assets, asset trading, fast transfers, traceability, and smart contracts to resolve these issues. This makes the CSU ecosystem more versatile and adaptable, becoming a fundamental application in the cloud computing field, ushering in a new era for cloud computing. It redefines an open-source blockchain protocol named CSU.