X.500 is an international standard for electronic directory services. It’s designed for supporting management and routing in distributed computing environments. It provides a consistent and system-independent method of creating and managing multiple types of resources, including files and devices, in a networked environment.


The phonetics for the keyword “X.500” is: “eks . fɪv hundred”

Key Takeaways

<ol><li>X.500 provides a global directory service that is used to support email exchange, user identification, and other network services. It is designed to centralize data and make it accessible to users around the world.</li><li>X.500 employs a hierarchical structure for managing directory information. This includes using Distinguished Names (DNs) for unique referencing and organizing entries based on geographic or organizational boundaries, known as Directory Information Tree (DIT).</li><li>While X.500 provides comprehensive functionality, its implementations can be complex and resource-intensive, leading to alternate lightweight solutions like LDAP. In comparison to X.500, LDAP excels in ease of use, simplicity, and web compatibility.</li></ol>


X.500 is a significant technology term as it refers to a series of computer networking standards that provide a comprehensive model for Directory Services. Developed by the International Telecommunication Union’s Telecommunication Standardization sector (ITU-T), X.500 standards are pivotal for defining how global directories should be structured and how the services should be used. Its primary role includes attributes like a global address book, aiding users to locate resources, and providing a basis for email systems to find information, including details of the target system and user. The influence of X.500 extends to its contribution to the development of the Lightweight Directory Access Protocol (LDAP), which is extensively used today. Thus, X.500 plays a crucial role in organizing and managing diverse network resources.


X.500 is a robust directory protocol primarily used for defining the structure and functionality of global directories in a network. Its main purpose is to standardize the way data is organized and retrieved, thereby streamlining data lookup processes across disparate systems. This feature promotes intercommunication between different directory services systems, forming an integrated system where information such as emails, usernames, and printer names are centrally stored and can be easily located and accessed.The emphasis on X.500’s purpose is on the delivery of comprehensive global directory services capable of supporting a wide range of applications. It is instrumental in providing a blueprint for creating directories used in various systems including email systems, network operating systems, and distributed applications. By outlining how data is categorized and arranged, users can perform a well-organized search, making it simpler and quicker to access necessary data. Therefore, the X.500 protocol remains a cornerstone in the creation of structured directories in various IT-related platforms, and plays a critical role in the daily operations of technology infrastructures globally.


X.500 is a series of computer networking standards that cover electronic directory services. Here are three real-world applications that make use of X.500 standards:1. LDAP (Lightweight Directory Access Protocol): LDAP is an open, vendor-neutral application protocol for accessing and maintaining distributed directory information services over an Internet Protocol (IP) network, which follows the structure of X.500.2. Email Systems: X.500 is extensively used in email systems. It helps in empowering the global address book facility where any user within the company can look up the email address of other users. Microsoft Exchange, for instance, utilizes the X.500 standard for this purpose.3. Telecommunication Networks: Telecom providers often apply X.500 directory service standards to manage distribution lists, user details, and other network-related services. This is especially prevalent in feature-rich enterprise communication systems.

Frequently Asked Questions(FAQ)

Q: What is X.500?A: X.500 is a series of computer networking standards covering electronic directory services. It is part of the X.500 series of protocols designed by the ITU and ISO from 1988 onwards.Q: What are X.500 directories?A: X.500 directories are a type of network service that stores information about network resources, which can be computers, printers, fax machines, applications, databases, users, or really any other type of network-accessible entity.Q: What is the purpose of X.500?A: The purpose of X.500 is to standardize methods for accessing information in a network. It provides a framework for global directories that operate in a consistent, predictable manner, thereby providing the foundation for a universally accessible directory service.Q: What protocol does X.500 use?A: X.500 uses the Directory Access Protocol (DAP), which communicates between directories and clients.Q: How does X.500 relate to LDAP?A: The Lightweight Directory Access Protocol, or LDAP, was developed as a simplified alternative to the DAP protocol used by X.500. LDAP retains much of X.500’s function, while reducing the resource requirements.Q: Is X.500 still in use?A: While X.500 and its DAP protocol are not commonly used today due to its complexity and high resource demands, its structure and principles are still largely mirrored in widely-used LDAP services.Q: What are the components of an X.500 directory?A: An X.500 directory has several components, including Directory User Agents (DUAs), Directory System Agents (DSAs), directory entries, and the Directory Information Tree (DIT).Q: What organizations developed X.500?A: X.500 was developed by the International Telecommunication Union (ITU) and the International Organization for Standardization (ISO).Q: What types of information can be stored in an X.500 directory?A: An X.500 directory can store a wide range of information, including but not limited to usernames, phone numbers, email addresses, printer locations, and file links.

Related Tech Terms

  • Directory Access Protocol (DAP)
  • Directory System Agent (DSA)
  • Lightweight Directory Access Protocol (LDAP)
  • Directory Information Tree (DIT)
  • Directory Information Base (DIB)

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