Active Directory, Second Edition

Windows NT Versus Active Directory

As we mentioned earlier, Windows NT and Active Directory both provide directory services to clients (Windows NT in a more generic sense). And while both share some common concepts, such as Security Identifiers (SIDs) to identify security principals, they are very different from a feature, scalability, and functionality point of view. Table 1-1 contains a comparison of features between Windows NT and Active Directory.

Table 1-1. A comparison between Windows NT and Active Directory

Windows NT	Active Directory
Single-master replication is used, from the PDC master to the BDC subordinates.	Multimaster replication is used between all domain controllers.
Domain is the smallest unit of partitioning.	Naming Contexts and Application Partitions are the smallest unit of partitioning.
System policies can be used locally on machines or set at the domain level.	Group policies can be managed centrally and used by clients throughout the forest based on domain, site or OU criteria.
Data cannot be stored hierarchically within a domain.	Data can be stored in a hierarchical manner using OUs.
Domain is the smallest unit of security delegation and administration.	A property of an object is the smallest unit of security delegation/administration.
NetBIOS and WINS used for name resolution.	DNS is used for name resolution.
Object is the smallest unit of replication.	Attribute is the smallest unit of replication. In Windows Server 2003 Active Directory, ...