Ad active directory and domain network

AD yes Active Directory, The active directory , Used to manage network resources .
AD It provides directory services , The directory service is CS Pattern , It can be regarded as a database .
Why not use traditional relational database to do this function , Instead, we should build a AD Well ？ Because it is characterized by more reading and querying , Few changes , The data structure is very similar to the hierarchy of the real world , Maintain the uniqueness of directory object names , Therefore, in view of these characteristics, we specially develop the most suitable thing , Directory service .
Catalogue and hierarchy in reality ：

The above features , It is suitable for some basic 、 Critical information management , For example, address book 、 Company personnel information 、 Organization 、 Computer network resources 、 Digital certificates and public keys, etc , These are suitable for directory database management .
Directory services also have Standards . One is X.500, Agreement is DAP（ Directory Access Protocol ）, It is not a factual standard , Factual standards and industrial standards are different , That's it LDAP.
see LDAP Directory hierarchy in ：

Use the identifying name of the directory entry （Distinguished Name DN） To read an entry . For example, this item ：

cn=zhong, ou=office, dc=abc, dc=com

It is from RDN（ Relative identification name ） + Recorded in the LDAP The location in the directory consists of . This order is the address order of foreign countries , Put the most detailed at the front . In fact, it is similar to the file name + File directory .

CN（Common Name） Is the leaf node at the end , This is the man zhong,OU（Organization Unit） It's the organizational unit , There can be many layers ,OU yes offcie,DC（Domain Component） It is a domain name component , There can also be multiple layers , here DC yes abc and com.

The top level of the directory is the root . Also known as basic DN. At present, the most commonly used format is to use the company's DNS domain name , such as o = abc.com. Can also be dc = com As a basic DN.
RDMS To define the table structure , What the catalog database needs to define is the object type of the catalog , Data objects can be represented by attributes .

Windows The network structure is as follows 2 Kind of ：Workgroup and Domain.
For small networks Workgroup. Computers in the network are all equal , Manage yourself , All computers have local security account databases （SAM database ）

For medium and large scale Domain, Centralized management .

Centralized management certainly has some benefits , Can solve workgroup Some disadvantages of network structure ：

1. A user account needs to be accessed on multiple calculations , The sheep management method is to create this user account on these computers one by one .
2. The security configuration should be set on multiple computers one by one

The computer wants to join the domain , Users can log in with a domain account on the computer , Otherwise, you can only log in with your local security account .