What is the domain controller?

Domain control (DM) concerns a computer system based on Microsoft Windows®, which stores user account data in the central database for its assigned domain. It uses these stored data to provide important services throughout the area, such as user verification, security principles, and access to resources. In essence, the domain controller allows the system administrator to grant any specific user access to certain system sources, printers-via username and password.

The first DM was implemented on Windows® NT through a database known as the security account administrator (SAM). This system is based on the primary domain controller (PDC) associated with one or more backup domain controllers (BDC). PDC processes all domain -related problems such as user authentication, while PDC only serves as backups for increased failure tolerance. If PDC sometimes fails, one of the BDC must be reconfigured to PDC.

Problem with Windows® NT HomeiThe controller model is that it is not scalp, which means that it can only be used for small business purposes. To alleviate this, Microsoft has replaced Sam, PDCS and BDC with Active Directory (AD). This technology changes the network into a large directory, like yellow pages, which is much easier to manage and control. Even more importantly, the Active Directory system allows more domains to work on the same level.

Each domain controller has a copy of the database and. In addition, all DC in the domain remains continuously synchronized by a process known as the replication of multiple masters. In this process, change information changes at any time, then the signal is transmitted to all other DCs to ensure that all information remains updated and correct. However, it may be important to realize that one DC serves as a master in that he is responsible for confirmation of all data modifications and any conflicts that may occur atEditing current data change requirements. If the master fails, another DC will immediately take over the role.

However, there is one main limitation of the Active Directory system. The domain controller must clearly host the Windows® operating system, which means that all other domain members or workstations must also use Windows®. This was fixed by the introduction of samba, Open-Source/Free Software Software Set, which allows workstations with other operating systems-likes is UNIX, Linux, IBM System 390 and OpenVMS-Pro interaction with domain controller. This gives a network administrator or engineer much greater flexibility. This is particularly useful in large corporations in which different departments require different operating systems.