Directory servers / Internet and Networking

Directory servers :-hold a list of the user accounts that are allowed to log on to the network.  This list of users accounts is stored in a database (known as the directory database)  and can store information about these user accounts such as address,  city,  phone number,  and fax number.  A directory service is designed to be a central database that can be used to store everything about such objects as users and printers.
          In a server-based network environment,  the centralized administration comes from the fact that the directory server stores all user accounts on its directory database.  When a user sits at a client machine to log on to the network, the login request is sent to directory server.  If the username and password exist in the directory database,  the client is allowed to access network resources. It is important to Korea that a server can have numerous roles at the same time.  A server can be a file and print server,  as well as an application server,  or it can be a file,  print,  and directory server all at the same time.  Because a single server can perform multiple roles,  a company will not need to purchase an additional server every time a very time a new product (or feature)  is implemented on the network,  and this fact reduces the cost of a server-basee network.