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What Is JNDI?

What is a naming service?

Naming services map objects with names. It maps a reference to an object by a user friendly name. For example a machine maps its ip address. The association of an object with a name is called 'binding'. Examples : Domain Naming Service, File systems.

What is a directory service?

Searching for files and directories done by providing Directory services. A directory service is a set of names. The user and resource information and machine addresses are summarized by directory service. For example, for a given user name, the service returns the attributes of the user such as telephone no, email address etc. A directory service use the databases that specialized and hierarchical in design.

What is LDAP?

LDAP stands for Lightweight Directory Access Protocol. This is a protocol for querying and modifying directory services over TCP/IP. LDAP is an application protocol . LDAP is used for accessing and updating information in a directory. These operations include establishing sessions and disconnecting sessions. LDAP has hierarchical data format. This hierarchy usually has domain names.
Uses of LDAP
  • A large no. Of machines can have a common list of login users.
  • Reading accesses and responsiveness is fast.
  • LDAP can be used to cluster when failover occurs.

How do we use LDAP to work with a directory service?

  • At the time of creation of the databases, the existing LDAP will receive the database server instance and the database information is provided to the LDAP directory after the creation of the databases.
  • The catalog information for the server can be retrieved for the directory of LDAP, at the time of the client's connection to the database.
  • The catalogue information need not be stored locally on each machine for the clients.
  • The LDAP directory will be searched by the client applications for the needed information in order to connect to the database.

Explain the importance of JNDI.

To centralize the information storage the enterprises uses LDAP. The information is of user names, passwords, email addresses, printers, determination of database access. Multiple database management is reduced by centralizing the information.

Explain why we need JNDI if communication to systems via LDAP is possible.

Most of the operations are with databases and servers in LDAP. Using JNDI multiple dbms can be reduced by centralizing the information. The centralization of information storage is done by LDAP.

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