You want to securely implement the Network Time Protocol (NTP) on your network. What two mechanisms are available to secure NTP? (Choose two.)

IPSec communication can secure general network traffic, but it is not a native or built-in authentication mechanism specific to the NTP protocol itself for securing its operations.

MD5 authentication keys provide a cryptographic method to verify the identity of NTP peers, ensuring that time synchronization messages are accepted only from trusted sources and protecting against unauthorized time modifications.

Role-based access control (RBAC) is an authorization model for managing user permissions to systems or applications, not a direct security mechanism for the NTP protocol's communication or time synchronization.

Access control lists (ACLs) or access-groups can be configured on network devices to filter incoming and outgoing NTP traffic, allowing administrators to define specific IP addresses or subnets that are permitted to query or provide NTP services, thereby limiting exposure.