The Windows Users and Groups Connector (in older versions of IBM® Security Directory Integrator this was called the NT4 Connector) operates with the Windows NT security database. You can use the information and links provided here to know more about it.
It deals with Windows users and groups (the two basic entities of the Windows NT security database). This Connector can both read and modify Windows NT security database on the local Windows machine, the Primary Domain Controller machine and the Primary Domain Controller machine of another domain.
The Connector is designed to connect to the Windows NT4 and Windows 2000 SAM databases through the Win32 API for Windows NT and Windows 2000/2003 user and group accounts. You can connect to a Windows 2000 SAM database, but the Connector only reads or writes attributes that are compatible with NT4 (in other words, the Windows Users and Groups Connector has a predefined and static attribute map table consisting of NT4 attributes). Windows 2000/2003 native attributes or user-defined attributes are therefore not supported by this Connector.
See Windows Users and Groups Connector functional specifications and software requirements for a full functional specification of the Connector, architecture description as well as hardware and software requirements.