Explanation
With dynamic masking, production environments are protected with the masking process being implemented between the application and data layers of the application. This allows for a masking translation to take place live in the system and during normal application processing of data.

Chillers and cooling systems are internal to a data center and its operations, and as such they are considered an internal redundancy. Power feeds, network circuits, and generators are all external to a data center and provide utility services to them, which makes them an external redundancy.

Explanation/Reference:
Explanation:
With cloud providers hosting a number of different customers, it would be impractical for them to pursue additional certifications based on the needs of a specific customer. Cloud environments are built to a common denominator to serve the greatest number of customers, and especially within a public cloud model, it is not possible or practical for a cloud provider to alter their services for specific customer demands.

Explanation
Reservations ensure that a minimum level of resources will always be available to a cloud customer for them to start and operate their services. In the event of a DoS attack against one customer, they can guarantee that the other customers will still be able to operate.