Just like almost everything else in Kubernetes, authorization is modular. We can choose to use Node, ABAC, Webhook, or RBAC authorization.

Node: Node authorization grants permissions to kubelets based on the Pods they are scheduled to run.

ABAC: Attribute-based access control (ABAC) is based on attributes combined with policies and is considered deprecated in favor of RBAC.

Webhooks: Webhooks are used for event notifications through HTTP POST requests.

RBAC: Role-based access control (RBAC) grants (or denies) access to resources based on roles of individual users or groups.