Answer:
Configure Caching on RODCs using PRP.
Step-by-step explanation
Read only domain controller is a domain controller that allows active directories for read only purposes. An administrator can setup RODCs for branches of a company and control the domain controller of the database server, updating the database which can be viewed as a read only partition in RODC.
Authenticating users in a RODC rely on the domain controller to forward the credentials to the read only domain controller. This can impose to high traffic on a slow WAN network link, especially when many users are trying to authenticate, resulting to high bandwidth.
To avoid this, credential caching by configuring password replication policy (PRP) on the RODC is vital.
When PRP is configure on RODC, the user only get to authenticate once, then the user password is replicated and encrypted for subsequent use.