Active Directory Overview
For my latest CBT Nuggets course, you and I are going on an intense exploration of the wonders of Active Directory (AD). AD is a Network Operating System (NOS) that Microsoft originally built on top of Windows 2000! Obviously, with Windows Server 2016 powering many data centers today, this NOS has seen many change and improvements.
It is fair to think of AD as a sophisticated database. It holds information about your users, groups, computers, printers, and any other objects you need to define in order to make your network thrive. When Microsoft first introduced Windows NT, they were struggling with what to do about a NOS. In fact, the original “domain” concept from Microsoft featured information stored in a flat file structure and constrained administrators to a fixed number of objects they could add to the domain. It is amazing to think about this today with the vastly scalable network architectures of Server 2016.
The key technology that changed everything for Microsoft was the Lightweight Directory Access Protocol (LDAP). Microsoft was so impressed with this open standard for NOS functions they based their own Active Directory on these principles and ensured the compliance of AD with LDAP.
It is no coincidence that LDAPv3 became a reality in 1997 and Microsoft released AD in Windows 2000.
The Database Revealed
While Active Directory presents a hierarchical structure to users and administrators, it is still actually stored in a flat file database structure. Users never see this, however. They see container objects and non-container objects (leaf nodes). The most common container we use today is the OU (OrganizationUnit). These incredibly powerful structures allow us to group similar objects and then apply security and management policies to these devices as a whole.