DAP - Directory Access Protocol

What is DAP?

DAP stands for Directory Access Protocol. It is a protocol used to access information stored in a directory service, such as X.500 directory services. It provides a standard way for users and applications to retrieve and manage directory information.

Why is DAP useful?

  • Allows access to distributed directory services.

  • Enables the retrieval of user, device, and resource information in large networks.

  • Supports complex queries and hierarchical data structures.

  • Promotes standardization in directory access.

How it works?

  • A client sends a DAP request to a directory server.

  • The directory server processes the request using X.500 standards.

  • The server returns the requested data or performs the requested action (e.g., search, read, compare).

  • Communication follows a strict data format defined in ASN.1 over OSI protocols.

Where is DAP used?

  • X.500 directory services in enterprise and government networks.

  • Legacy systems requiring detailed directory-based authentication and identity services.

  • Environments where complete OSI model protocol stacks are used.

Which OSI layer does this protocol belong to?

  • DAP operates at the Application Layer (Layer 7) of the OSI model.

  • It defines how clients interact with directory services, relying on lower OSI layers for data transport.

IS DAP Windows specific?

  • No, DAP is not Windows-specific.

  • It is a platform-independent protocol defined as part of the OSI suite, though it is less common today.

IS DAP Linux Specific?

  • No, DAP is not Linux-specific.

  • It can be implemented on any operating system that supports OSI protocol stacks.

Which Transport Protocol is used by DAP?

  • DAP typically uses OSI transport protocols, such as TP4.

  • In some implementations, it may run over TCP/IP via a gateway or adaptation layer.

Which Port is used by DAP?

  • DAP itself does not use traditional TCP/IP ports.

  • It operates over OSI protocols, but when tunneled through TCP/IP, it may use port 102 for the OSI transport service.

Is DAP using Client server model?

  • Yes, DAP uses the client-server model.

  • Clients send directory access requests to directory servers, which process and respond to those requests.

Topics in this section,

  • In this section, you are going to learn

  • Terminology

  • Version Info

  • rfc details

  • setup

  • setup

  • packet details

  • usecases

  • features

  • Reference links