Active Directory and Benefits.

What is Active Directory ?
" Active Directory is directory service, Microsoft developed and introduced in windows 2000 Server. It is only used in Microsoft windows domain network environment for security, easy administration and with set of process and services. It provides a centralized authentication service for Microsoft networks". Some of the benefits of Active Directory include a hierarchical organizational structure, Multi-Master authentication (the ability to access and modify AD from multiple points of administration) to create fault tolerance and redundancy, a single point of access to network resources.

Active Directory contains user, computers, groups, sites, organization units, servers, domain controllers, printers and applications. All these we can access from  Start --> Administrative tools
Active Directory Users and Computers,
Active Directory Domains and Trusts and
Active Directory Sites and Services.

A  Directory  Service allows businesses to define, manage, access, and secure network resources, including files, printers, people, and applications. Without the efficiency of a directory service, businesses would have difficulty keeping up with demands fr fast-paced data exchange. As corporate networks continue to grow in complexity and importance, businesses require more and more from the networks that facilitate this automation.

The Active Directory benefits are

1. Centralized resource and security administration

2. single logon for access to global resources

3. Fault tolerance and redundancy

4.Simplified resource location. 

Centralizing Resource and Security Administration:

 Active Directory provides a single point from which administrators can manage and access network resources and their associated security objects. An organization can administer Active directory based on an organizational model, a business model or the types of functions being administered. For example, an organization could choose to administer Active Directory by logically dividing the users according to the departments (by creating the OUs) in which they work, their geographical location (by creating the sites) or a combination of these characteristics.

Providing a Single Point of Access t Resources:

Prior to the introduction of directory services into corporate networks, all users were required t log n to many different servers in order t access a variety of different resources. This required users to enter their authentication information multiple times and an administrator had to maintain duplicate user accounts n every server in the organization. Imagine how enormous the tasks of managing a separate username and password n each server would be if your organization contained 10 servers and 10 users per server. Now imagine how much more difficult that would become with 10 servers and 500 users per server. You would have to create and maintain 5,000 user accounts, with all of the associated security assignments, if you were maintaining separate authentication for each individual server.

Fault Tolerance and Redundancy:

A system is said t be fault tolerant if it is capable of responding gracefully t a software or hardware failure. For example, a server is fault tolerant if it can continue to function when a power supply or a hard drive suffers a mechanical failure. An authentication system such as active Directory is considered fault tolerant when it has the ability to continue providing authentication service even if one or more servers that provide authentication services (in the case of AD DS domain controllers) experience hardware failure or a loss of network connectivity. In this way, Active Directory can offer a redundant solution which can continue to provide authentication services without any adverse effects noticed by users, workstations, or other applications or services. 

Active Directory builds in fault tolerance through its multimaster domain controllers design. This fault tolerance is created due t the fact that all domain controllers in an Active Directory domain share a common database file called ntds.dit; any change that is made on one domain controllers is replicated to all other domain controllers in the environment. This ensures that all domain controllers have consistent information about the domain.

Simplifying Resource Location:

Imagine you are a user in a 10-server environment, where every server has a different set of resources that you need to do your job. If you were in this situation, identifying which server provided each resource would not be an easy task. This is even more complicate4d when you have mobile users, such as an employee visiting from another site who needs to locate printers and other devices to become productive at the new site.

Active Directory simplifies this process by allowing file and print resources to be published on the network.  Publishing an object  allows users t access network resources by searching the Active Directory database for the desired resource.

We have many more benefits and feature of Active Directory based on Server versions and domain and forest functional levels.

Guys feel free to ask questions about active directory you can write below at comments section, I will get back to you as soon as possible....