• Multiple KDCs can be used to avoid a performance bottleneck at the KDC.
• Updates are sufficiently rare that the master copy will be easily capable of
keeping up with all updates.
• Most of the operations will be read-only, and these operations will be spread
among the read-only replicas.
• Another reason that replication may improve performance is so that a KDC
replica is usually nearby.
• When downloading the KDC database from the master replica to a read-only
slave, it is important to protect the data from disclosure and modification.
• Disclosure would permit an attacker to learn the master keys of all principals
• Modification would permit an attacker to create new accounts or change the
properties of existing ones.
• This protection could have been provided by encrypting the KDC database as a unit
when it was being transferred.