Explain in your own words how remote-access Trojans (RATs) work. How can these be used by attackers? How would a network administrator know if one is on his/her network?

Answer: Remote Access Trojans (RATs) is the malware that is used by the hackers to attack the computer and operating system remotely. The working of RATs is done by download the malware and executing it to create a server. After the server is created, hacker sends this server along with a crypter to eliminate the antivirus program's function present in the user's system.

Thus, RAT gets invoked in the system of the user and the hacker can control the user's system. Attacker can hack the complete functioning of the user's system and can steal, destroy, execute etc any confidential data and application.

The user or the network administrator can get to know about the RAT's activity by steps like checking the open port, checking the activities through Task Manager of Windows, observing any unusual activity and appearance of the display screen etc.