Access Control Entry

Definition of Access Control Entry

An Access Control Entry (ACE) is a component of the access control system that defines and manages the specific permissions granted or denied to individual users or groups. It is typically found within an Access Control List (ACL), which is a collection of ACEs. These entries determine the level of access allowed to various resources, such as files, directories, or network shares, allowing for secure and customized access management.


The phonetics of the keyword “Access Control Entry” in the International Phonetic Alphabet (IPA) are:/ˈæ kənˈtroʊl ˈen.tri/Here is the phonetic representation of each word separately:Access – /ˈæ – /kənˈtroʊl/Entry – /ˈen.tri/

Key Takeaways

  1. An Access Control Entry (ACE) refers to an individual entry in an Access Control List (ACL), which determines the permissions granted or denied to specific users or groups for accessing resources within a system.
  2. ACEs store the security identifier (SID) of a user or group, as well as the specific access rights granted, such as read, write, or execute permissions. This allows for fine-grained control over access to resources.
  3. Modifying or managing ACEs is essential for maintaining proper security and ensuring that only authorized users have access to the necessary resources. This involves regularly reviewing and updating ACLs, and following best practices for access control management.

Importance of Access Control Entry

The technology term Access Control Entry (ACE) is important because it plays a crucial role in maintaining the security and privacy of a system’s resources, such as files and directories.

ACE is a component of the Access Control List (ACL), which defines the permissions granted to various users or groups for accessing a specific resource.

By specifying the privileges, such as read, write, or delete, in the Access Control Entry, system administrators can ensure that only authorized individuals have access to sensitive information or perform specific operations.

This fine-grained control contributes to the overall integrity and protection of the system, helping to prevent unauthorized access, data breaches, and potential misuse of resources.


Access Control Entry (ACE) serves a vital purpose in computer security by managing and restricting access to critical resources or sensitive information. Its primary goal is to establish high-level data protection for various objects such as files, folders, and network shares.

This technology component ensures that only authorized users or entities can interact with these resources according to the specified access permissions. In doing so, ACE helps maintain the integrity, confidentiality, and availability of data, preventing unauthorized access or potential misuse.

To accommodate the various needs of organizations and maintain a cohesive structure for data management, Access Control Entries are often implemented within Access Control Lists (ACLs). An ACL is a collection of ACEs that dictates who can access a specific object and the type of actions that they can perform, such as read, write, delete, or modify. By incorporating ACEs into a comprehensive access control framework, system administrators can effectively manage user permissions and maintain a secure environment that meets the organization’s data protection standards.

The consistent use of Access Control Entry mechanisms is a proactive step towards ensuring reliable data security and mitigating potential risks associated with unauthorized access.

Examples of Access Control Entry

Access Control Entry (ACE) is a crucial component of access control systems and is widely used in various real-world scenarios to enhance security by managing permission levels for specific resources or assets. Here are three real-world examples of ACE implementation:

Corporate Offices: In large organizations, ACE is implemented within the internal network to restrict or grant access to selective documents, folders, and applications. Employees are assigned different access levels based on their role and hierarchy to prevent unauthorized access, safeguard sensitive information, and maintain a secure working environment.

Healthcare Institutions: Hospitals and healthcare organizations deal with sensitive patient information daily. To protect the privacy of patients and to comply with industry regulations (such as HIPAA), healthcare institutions use ACE to manage permissions for accessing and updating Electronic Health Records (EHR). This ensures that only authorized personnel, including doctors, nurses, and administrative staff, have the appropriate access to patient information based on their specific roles.

Banking and Financial Institutions: To maintain the confidentiality and integrity of their customers’ financial data, banks and financial institutions leverage ACE technology. By implementing ACE rules in their server and network infrastructure, they ensure that only authorized employees have access to specific resources, systems, or databases. This helps in mitigating risks from insider threats and external cyber attacks while complying with industry regulations such as GDPR, PCI-DSS, and other data protection standards.

Access Control Entry FAQs

1. What is an Access Control Entry (ACE)?

An Access Control Entry (ACE) is a component of an Access Control List (ACL) that defines access rights or permissions for a specific user or group to a secured resource.

2. What are the main components of an ACE?

An ACE consists of a Security Identifier (SID) representing the user or group, an Access Mask defining the permissions, and a set of ACE flags and type indicators, such as inheritance and auditing information.

3. What is the function of an Access Control List (ACL) in access control?

An Access Control List (ACL) is a collection of multiple Access Control Entries (ACEs) that work together to define access permissions and restrictions for a particular secured resource.

4. What are different types of ACEs?

There are various types of ACEs, such as Access-Allow ACE, Access-Deny ACE, and System Audit ACE. Access-Allow and Access-Deny ACEs grant or deny access permissions, while System Audit ACEs record access attempts for security auditing purposes.

5. How does an ACE impact access decisions for a secured object?

An Access Control Entry (ACE) becomes effective when the Access Control List (ACL) in which it is contained is evaluated during the process of requesting access to a secured object. The system evaluates each ACE to determine if the specified user or group will be allowed or denied access based on the permissions set in the Access Mask field.

Related Technology Terms


  • Permissions
  • Authentication
  • Authorization
  • Access Control List (ACL)
  • Role-Based Access Control (RBAC)


Sources for More Information


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