Limit information system access to the types of transactions and functions that authorized users are permitted to execute.
Monarch ISC Guidance
Role Based Access Control is best achieved by utilizing security groups. While the use of user level permissions may achieve compliance with this practice, we suggest always using security groups. Regardless of how you do it, you will need to limit access to applications and files to only those users with the business requirement to access those resources.
Place users in appropriate groups for their department, location, or application need, and then use those groups to permit (or deny!) access to file shares, applications, and other network resources such as printers.
Create a policy stating the organizational requirement is to limit user access to the resources required to perform their duties and document the various roles used.
DRAFT NIST SP 800-171 R2
Organizations may choose to define access privileges or other attributes by account, by type of account, or a combination of both. System account types include individual, shared, group, system, anonymous, guest, emergency, developer, manufacturer, vendor, and temporary. Other attributes required for authorizing access include restrictions on time-of-day, day-of-week, and point-of-origin.
In defining other account attributes, organizations consider system-related requirements (e.g., system up grades scheduled maintenance,) and mission or business requirements, (e.g., time zone differences, customer requirements, remote access to support travel requirements).