Any DIT supported service can be used to store Level 1: Low data. For example, Google Drive can store and share Level 2 and Level 1 data.
Given the risks and obligations with level 4 data, any new data storage at this level must be discussed on an individual basis with DIT Security, DIT Privacy, and Research Security (Research Data) or Management Advisory Services (Admin Data) before any data is stored. Most of the data at this level requires individual handling plans such as setting appropriate permissions, user access, and documentation. If you have any questions regarding the security assessment process, please contact it-compliance@umd.edu.