ACL - Access Control List

A list of permissions, defining who is allowed access to what resources (eg: files, folders, functionality).

An ACL is essentially a map, listing users (or groups of users), and what permissions they have.

Access Control Lists typically use a minimum of 2 permissions: read and write.

In more advanced systems, such as operating systems, more permissions are available, such as:

• the permission to execute a script or program
• the permission to act as part of the operating system

In a Wiki, permissions such as the following are used:

• view page
• edit page
• rename page
• delete page
• comment on page

ACL's can look very different depending on the system they are protecting.

An simple example of an Access Control List, extracted from a Subversion repository is shown below. In this case, there is a resource called /TheProject, which is a folder.

[/TheProject]
neale=rw
cassie=r

As can be seen, the user neale has read and write (rw) access, while cassie only has read (r) access.