Authentication Process

Active Directory Authentication Process (Kerberos-based)

1. User Logon

• User enters credentials (username + password).

• Example: [e-mail].

2. AS Request (Authentication Service)

• The client sends a request to the KDC (Key Distribution Center) to get a TGT (Ticket Granting Ticket).

• The KDC resides on the Domain Controller.

3. Verification & TGT Issuance

• The KDC validates the user's credentials.

• If correct, it returns a TGT, encrypted with the KDC’s secret key.

4. TGS Request (Ticket Granting Service)

• The client uses the TGT to request access to a specific service (e.g., file share).

• It sends the TGT to the TGS component of the KDC.

5. Service Ticket Issuance

• The TGS verifies the TGT.

• If valid, it issues a Service Ticket for the requested service.

6. Service Access

• The client presents the Service Ticket to the target service (e.g., File Server).

• If valid and authorized, access is granted.

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