Abstract—Public cloud storage services offer convenient file sharing and backup services. However, many enterprises have been wary to employ these services and some even prohibit their employees from using such services for business data due to concerns over privacy, security, control of their assets, and vendor lock-in issues. To address these issues, this work proposes a new service utilization model (an architecture), which virtualizes public storage services among multiple user accounts to provide each user with a more secure, better HA (High Availability), and more fixable storage service.