Simplify the following text for a Grade 11 native English-speaking person.
Original: Kerberos database : The key distribution center ( KDC ) maintains a database of secret keys ; each entity on the network â '' whether a client or a server â '' shares a secret key known only to itself and to the KDC .
Simplified: The KDC maintains a database of secret keys ; each entity on the network -- whether a client or a server -- shares a secret key known only to itself and to the KDC .