Download Active directory

A centralized system
 Active
Directory is Microsoft's trademarked
directory service, an integral part of the
Windows architecture. Like other directory
services, such as Active Directory is a
centralized and standardized system that
automates network management of user
data, security and distributed resources and
enables interoperation with other
directories. Active Directory is designed
especially for distributed networking
environments.
 Active
Directory was new to Windows 2000
Server and further enhanced for Windows
Server 2003, making it an even more
important part of the operating
system. Windows Server 2003 Active
Directory provides a single reference, called
a directory service, to all the objects in a
network, including users, groups, computers,
printers, policies and permissions.
 For a user or an administrator, Active
Directory provides a single hierarchical view
from which to access and manage all of the
network's resources.
 There
are many reasons to implement Active
Directory. First and foremost, Microsoft
Active Directory is generally considered to be
a significant improvement over Windows NT
Server 4.0 domains or even standalone server
networks. Active Directory has a centralized
administration mechanism over the entire
network. It also provides for redundancy and
fault tolerance when two or more domain
controllers are deployed within a domain.
 Active
Directory automatically manages the
communications between domain controllers
to ensure the network remains viable. Users
can access all resources on the network for
which they are authorized through a single
sign-on. All resources in the network are
protected by a robust security mechanism
that verifies the identity of users and the
authorizations of resources on each access.

Even with Active Directory's improved security
and control over the network, most of its
features are invisible to end users; therefore,
migrating users to an Active Directory network
will require little re-training. Active Directory
offers a means of easily promoting and demoting
domain controllers and member servers. Systems
can be managed and secured via Group Policies.
It is a flexible hierarchical organizational model
that allows for easy management and detailed
specific delegation of administrative
responsibilities. Perhaps most importantly,
however, is that Active Directory is capable of
managing millions of objects within a single
domain.
 Active
Directory networks are organized
using four types of divisions or container
structures. These four divisions are forests,
domains, organizational units and sites.




Forests: The collection of every object, its attributes
and attribute syntax in the Active Directory.
Domain: A collection of computers that share a
common set of policies, a name and a database of
their members.
Organizational units: Containers in which domains
can be grouped. They create a hierarchy for the
domain and create the structure of the Active
Directory's company in geographical or organizational
terms.
Sites: Physical groupings independent of the domain
and OU structure. Sites distinguish between locations
connected by low- and high-speed connections and
are defined by one or more IP subnets.
 Microsoft
includes LDAP (Lightweight
Directory Access Protocol) as part of Active
Directory. LDAP is a software protocol for
enabling anyone to locate organizations,
individuals and other resources such as files
and devices in a network, whether on the
public Internet or on a corporate intranet.
 In
a network, a directory tells you where in
the network something is located. On TCP/IP
networks (including the Internet), the
domain name system (DNS) is the directory
system used to relate the domain name to a
specific network address (a unique location
on the network). However, you may not know
the domain name. LDAP allows you to search
for individuals without knowing where
they're located (although additional
information will help with the search).
 An
LDAP directory is organized in a simple
"tree" hierarchy consisting of the following
levels:
 The root directory (the starting place or the
source of the tree), which branches out to
 Countries, each of which branches out to
 Organizations, which branch out to
 Organizational units (divisions, departments
and so forth), which branch out to (include
an entry for)
 Individuals (which include people, files and
shared resources, such as printers)

It will provide fully integrated security in the
form of user logon's and authentication.
2. It makes easy in administration in the form of
group policies and permissions.
3. It makes easy to identify the resources.
4. It will provide scalability and flexibility
5. It is tightly integrated with DNS services for
all its operations, which will provide better in
identifications and migrations.
 6.
It services will provide Automatic
replication of information between
the domain controllers.
7. It supports integration of the other
directory services also.
8. It supports multiple authentication
protocols.