What is Kerberos in Security+?
D1 · General · CompTIA Security+ SY0-701Kerberos is a network authentication protocol that uses encrypted tickets to authenticate users and services without transmitting passwords over the network.
Key components: KDC (Key Distribution Center) — the trusted authority; TGT (Ticket Granting Ticket) — proves identity to the KDC; Service Ticket — grants access to a specific resource.
Flow: Client → KDC (AS): "I'm Alice" → KDC issues TGT → Client presents TGT to get Service Ticket → Client presents Service Ticket to access resource.
Key components: KDC (Key Distribution Center) — the trusted authority; TGT (Ticket Granting Ticket) — proves identity to the KDC; Service Ticket — grants access to a specific resource.
Flow: Client → KDC (AS): "I'm Alice" → KDC issues TGT → Client presents TGT to get Service Ticket → Client presents Service Ticket to access resource.
Kerberos requires synchronized clocks (within 5 minutes) to prevent replay attacks. It's the default authentication protocol in Active Directory. Port 88. "Golden ticket" and "silver ticket" attacks target Kerberos.