The History of Active Directory

Active Directory (AD) was introduced in Windows 2000 Server as a way to centralize authentication and management in Windows networks. Before AD, Microsoft used NT Domains, which were… well, kind of a mess compared to AD’s hierarchical structure.

Why Was Active Directory Created?

• Simplify user and resource management → Centralized authentication and permissions.
• Scalability → Allowed organizations to manage millions of objects in a network.
• Integration with Internet Standards → Added support for LDAP, DNS, and Kerberos authentication.

Key Features of Active Directory

✅ Hierarchical Structure → Users, groups, computers, and policies are stored in a tree-like structure.
✅ Single Sign-On (SSO) → Users log in once and access multiple resources.
✅ LDAP Integration → AD implements LDAP, making it compatible with non-Microsoft systems.
✅ Group Policies (GPOs) → Enforce security and configuration settings across an organization.

Further Reading:

• Active Directory Wikipedia
• Microsoft Docs: Active Directory Overview

Active Directory vs. LDAP

Active Directory is often confused with LDAP, but they are not the same thing.

💡 Verdict: LDAP is a protocol, while Active Directory is a Microsoft directory service that uses LDAP.

Active Directory Code Examples

1. Query Active Directory Using PowerShell

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Get-ADUser -Filter * | Select-Object Name, SamAccountName, Enabled

2. Create a New AD User (PowerShell)

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New-ADUser -Name "John Doe" -GivenName "John" -Surname "Doe" -SamAccountName "jdoe" -UserPrincipalName "jdoe@domain.com" -Path "OU=Users,DC=domain,DC=com" -Enabled $true

3. Query Active Directory Using LDAP in Python

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import ldap

conn = ldap.initialize("ldap://your-ad-server")
conn.simple_bind_s("admin@domain.com", "password")

search_base = "DC=domain,DC=com"
search_filter = "(objectClass=user)"
attributes = ["cn", "mail"]

result = conn.search_s(search_base, ldap.SCOPE_SUBTREE, search_filter, attributes)
for dn, entry in result:
    print(entry)

4. Query AD Using C# (System.DirectoryServices)

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using System.DirectoryServices;

DirectorySearcher search = new DirectorySearcher(new DirectoryEntry("LDAP://domain.com"));
search.Filter = "(objectClass=user)";
foreach (SearchResult result in search.FindAll())
{
    Console.WriteLine(result.Properties["cn"][0]);
}

5. Check If a User Exists in AD (PowerShell)

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Get-ADUser -Identity jdoe

6. Delete an AD User (PowerShell)

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Remove-ADUser -Identity "jdoe" -Confirm:$false

7. Enable an AD User Account (PowerShell)

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Enable-ADAccount -Identity "jdoe"

8. Disable an AD User Account (PowerShell)

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Disable-ADAccount -Identity "jdoe"

9. Add a User to a Group (PowerShell)

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Add-ADGroupMember -Identity "Administrators" -Members "jdoe"

10. Retrieve Group Memberships of a User (PowerShell)

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Get-ADUser jdoe -Property MemberOf

Key Takeaways

• Active Directory is Microsoft’s directory service, but it uses LDAP under the hood.
• ADSI (Active Directory Service Interfaces) allows programmatic access to AD in Windows environments.
• PowerShell, Python, and C# can all interact with Active Directory using LDAP or ADSI.

References

1. Active Directory Wikipedia
2. Microsoft Docs: Active Directory Overview
3. LDAP Wikipedia
4. PowerShell AD Cmdlets