Question

Regarding Operating Systems

Researchers have suggested that, instead of having an access control list associated with each file (specifying which users can access the file, and how), we should have a user control list associated with each user (specifying which files a user can access, and how). Discuss the relative merits of these two schemes.

Answer 1

In Operating Systems (OSs), with respect to the file system interface, on how it should be designed, developed, and implemented:
* In the case of, having an Access Control List (ACL) associated with each file, thus called, File Control List (or File Access Control List or Filesystem ACL), which would require specifying which users can access the file, and how, the ACL of permission, privileges, access rights, and information are centralized attached or associated to a file, which is an advantage, and the benefit is, it gives convenience; is simple, easy, and quick to change access control and permission information at one single place, and this consumes less memory space. Another benefit is it manages groups of users and inheritance in a hierarchy of groups. Also, it is powerful.

* In the case of, having a User Control List associated with each user which would require specifying which files a user can access, and how, this does not require more overhead in efforts, computation, or cost when accessing and opening a file.