Now that we have a basic understanding of networking, lets try to understand a corporate internal network, which consists of the following:
- Networking devices
- Hosts devices such as laptop/ desktop
- Security devices such as firewalls, IDS, IPS etc.
- Users and Groups
- Access control
- Applications & Data
Corporate organizations use centralized access control and directory services aids them with the same.
- A directory service (similar to a DB) offered by Microsoft
- Consists of Users, Groups, ACLs, Domains, Trusts etc.
- Stores user information such as user names, user ids, passwords, rights, relations etc.
- Provides access control, authentication, and centralized management for the administrators
- A network area that is under control of a single authentication database (i.e. the directory)
- A logical grouping of entities such as users, computers, servers etc. in a network
- Server (server role) where the directory is hosted
- Queried via LDAP for extracting information
- Usually a cluster of servers where one of them is a Primary DC and other Secondary (master and slave)
- Domain Users accounts, assigned to users, part of AD, administer by Domain Admins
- Domain Admins, privileged users accounts on the AD, administer the entire AD
- Machine accounts, assigned to the laptops, desktops, servers
- Service accounts, assigned to applications and services
- Local Users accounts, part of the machine, usually access limited to non-domain resources only, administered by local admins
- Local Admin accounts, privileged user accounts on local machine, however, these accounts can be administered by domain administrators
- Lightweight Directory Access Protocol, a protocol that provides a way to access data stored in the directory
- Fetch information from the directory
- Domain-based authentication and authorization is facilitated by NetNTLM and Kerberos
- Host access is facilitated by LSA and Credential Manager
- Application such as web services access is facilitated by Digest Authentication, Basic Authentication, Kerberos, etc.
- AD: NTDS.dit at the primary Domain Controller
- Host: SAM, LSASS, etc.
- Application: SSO, Application Databases, etc.