Cloud service is called an industrial revolution of the 21st century. It enables us to open documents stored in our computers at anytime and anywhere using various devices. It also enables more than two people to simultaneously access the system and work on documents. Like this, it is very convenient, but it is also vulnerable to security issues. Electronics and Telecommunications Research Institute (ETRI) has recently developed Cloud DaaS system that cuts off all the sources of hacking, using domestic SW technologies. As this system has strong security functions, it will no longer separately need storage devices or high-function computers when cloud servers are commercialized. We introduce the cloud system that will change the landscape of the future ICT industry.