An ACE is an access control entry.
The following list shows the currently defined ACE types:
| Ace Type | Structure | Type |
| AccessAllowed | ACCESS_ALLOWED_ACE | Discretionary Access Control |
| AccessDenied | ACCESS_DENIED_ACE | Discretionary Access Control |
| SystemAlarm | SYSTEM_ALARM_ACE | System Security |
| SystemAudit | SYSTEM_AUDIT_ACE | System Security |
More types may be added in the future.
An access control list, or ACL, contains a list of ACEs.
Each ACE type starts with an ACE_HEADER structure. The format of the data following the header varies according to the ACE type, which is specified in the header. The various ACE data structures are designed to provide optimal performance when they are longword aligned (32-bit boundaries).
ACL, ACCESS_ALLOWED_ACE, ACCESS_DENIED_ACE, SYSTEM_ALARM_ACE, SYSTEM_AUDIT_ACE