The Decision to Centralize Logon Services

Modern network server operating systems track user accounts in a secure and replicated database called a directory. The operating system services that facilitate the use of this database are called Directory Services. A domain is the administrative unit of Windows NT Server Directory Services. Within a domain, an administrator creates one user account for each user which includes user information, group memberships and security policy information.

Refer to the Terra Flora network diagram. At Terra Flora, three domains have been set up. They are the California Domain, the North East Domain and the Europe Domain.

Within each domain, domain controllers manage all aspects of user-domain interactions. Domain computers are computers running Windows NT Server that share one directory database to store security and user account information for the entire domain. Domain controllers use the information in the directory database to authenticate users logging on to domain accounts. Trust relationships are then set up between the domains to allow users in one domain to logon automatically to another domain. For details on how to manage the user work environment and domains, see Microsoft Windows NT Server 4.0 Concepts and Planning, Chapter 1, "Managing Windows NT Server Domains," Chapter 2, "Working with User Group Accounts" and Chapter 3, "Managing User Work Environments."

Currently, each of the heterogeneous networks in Terra Flora has its own security system through which the user signs onto the system and is authenticated to use the resources for which permissions are granted. One of the major complaints of network users is that they have to use multiple user accounts and passwords to sign onto different networks. Additionally, because there was no communications between networks, the users are required to log off one network to log onto another network.

At Terra Flora, the following steps have already been completed:

Following the steps in the remainder of the chapter will provide the user with the ability to logon onto the network from any computer in the network and, if the accounts, passwords and permissions have been granted on all network platforms, will provide access to all the user's required network resources.

For the user, the single network logon will provide transparent, seamless access to the network resources. For example, a NetWare user will logon as usual to the NetWare network and be authenticated to the Windows NT network at the same time. It will just happen and the user will not know that a different network has been accessed. An additional benefit to the user is the ability to sign onto all appropriate network resources from any computer on the network.

For Terra Flora, this consistent interface helps to easily integrate the business processes available through applications stored on servers on different networks, reduces training and reduces support costs as it all appears to the user as the same network system, and reduces the administration costs associated with setting up and maintaining separate logon accounts and passwords on each separate network.

The following sections include information on installing and configuring network logon services to allow authentication of: