Kerberos separation of duties is the design choice that keeps privileged access from collapsing into a single point of failure. In secure networks, Kerberos issues tickets for authentication. Without separation of duties, one administrator could hold both the ability to manage the Key Distribution Center (KDC) and control the service accounts. That convergence is a risk. It means compromise once equals compromise everywhere.
Separating duties breaks that risk apart. One role manages the KDC—generating and maintaining the master keys, handling ticket-granting services. Another role manages the application or service accounts—mapping identities, configuring permissions, rotating service passwords. By enforcing this split, no single role can impersonate any user or service without detection.
Kerberos separation of duties also reduces insider threats. A malicious KDC admin cannot deploy their own service account and pivot across the domain. A service admin cannot alter ticket issuance. Together, but apart, they lock the system from both ends.