This document shows you how to use the NFSv4 ACL permissions system. An ACL is a list of permissions associated with a file or directory. These permissions allow you to restrict access to a certian file or directory by user or group. NFSv4 ACLs provide more specific options than typical POSIX read/write/execute permissions used in most systems.
Understanding NFSv4 ACL
This is an example of an NFSv4 ACL