Explanation:
Three-tier architecture is a well-established software application architecture that organizes applications into three logical and physical computing tiers: the presentation tier, or user interface; the application tier, where data is processed; and the data tier
Answer:
Interface
Explanation:
An interface is the communication connection between two or more computers in a network that allows sharing of information or data between each components of the network such as computer peripheral device and software.
The main reason for data backup is to save important files if a system crash or hard drive failure occurs. There should be additional data backups if the original backups result in data corruption or hard drive failure.Additional backups are necessary if natural or man-made disasters occur