KDC
termsecuritynetworking
Key Distribution Center: the Kerberos authority - Authentication Service plus Ticket-Granting Service - that verifies principals and issues the TGT and service tickets; in Active Directory it runs on the domain controllers.
Clients talk to the KDC at login and when first reaching each service; after that, tickets verify offline, which is why KDC placement and time sync matter more than KDC throughput.
Also known as: Key Distribution Center