LDAP Directories

LDAP is now found in just about every medium to large-scale network today. If you are running NDS (or the eDirectory) or Microsoft Windows 2000 or .NET Server, then using LDAP can make managing the network a much simpler task than trying to manage separate islands of data stored on many computers. In today's business environment where companies are merging, using LDAP to store user and application information is almost a necessity. LDAP enables the network administrator to consolidate information into a logical hierarchical database, a much simpler task than in years past.

Windows 2000 and NetWare Are Not the Only Choices You Have

In past years the two primary contenders for your network dollars have been Microsoft and Novell. Although NetWare 6.x still includes NDS, now called the eDirectory, it appears that Novell is moving away from its core application services and directory services. Although the eDirectory will probably be around for a few more years to accommodate existing users, the company appears to be focusing now on Internet services, as evidenced by its iPrint and iFolder products. While Microsoft is trying to pull together a wide assortment of technologies by using the Active Directory, Novell is now trying to break apart its offerings into separate pieces so that you can choose what you like. The marketplace will determine who will succeed in this ongoing saga.

Yet, as a network administrator, you need not feel that you are constrained by Microsoft or Novell. Directory services are going to be here for quite some time until someone thinks up a better way to make locating and using network resources an easier task. Many other vendors , such as Netscape, jumped into the fray early on, and you will find that if you do not want to be locked into any particular vendor, there are other solutions. Another popular directory server product, iPlanet, was recently acquired by Sun Microsystems, and is now part of the Sun Open Net Environment “Sun ONE.

Using a search engine, you can find a large number of software vendors that now offer LDAP directory servers. If you don't want to make a large investment in a directory server, or you just want to learn about directory services, you can download the source code and documentation for the OpenLDAP directory server at www.openldap.org.

Sticking to Standards: Interoperability Between Directories

LDAP was developed to be a standard method for accessing a directory database. Just as TCP/IP allows data transfers and interoperability between different operating systems, the goal of LDAP is to do the same thing for directories.

However, while the structure of the database (the schema) and the protocol for a directory server are defined by the LDAP standards, that doesn't guarantee that all directory server products will easily interact with one another. This will probably change in the future as directories become more important in the corporate environment.

Import and Export Utilities

The LDAP Data Interchange Format (LDIF) is a specification that lets you export data from an LDAP-compliant directory to a flat-file, and then import the data into another directory. LDIF enables you to specify a point in the directory structure from which the export will be performed, and you can also filter selected objects or attributes. Most directory server products support LDIF, including Microsoft's Active Directory and Novell's eDirectory.

Metadirectories

In some cases you might find it desirable to maintain different directory servers instead of using LDIF to import data into a single server. For example, following the acquisition of another company, it may be impractical to integrate data into a single directory server product. Or it may be that each directory server provides features, all of which you want to keep. Another reason for maintaining multiple directory products is the cost of training network personnel on new applications. By keeping the same directories in place, business as usual can continue in today's fast-paced business world. Lastly, one of the features that a metadirectory product can provide is the capability to interface with data stores other than LDAP-based directories. Some applications, such as email products, were not written to work with LDAP servers but can be easily managed using a metadirectory product.