A company's business system received a flood of requests and stopped responding, so users could not use it when they needed to. Which of the three elements of information security (confidentiality, integrity, availability) was mainly compromised?

Answer: C. Availability

The three basic elements of information security are confidentiality, integrity and availability, known as the CIA triad from their initials. Confidentiality means only authorized people can access the information; integrity means the information is accurate and has not been altered without authorization; availability means authorized people can use the information and systems when they need them. In this case no information was leaked or altered; the system simply could not be used when needed, so availability was compromised. Measures that improve availability include redundant equipment, backups and load distribution. In addition to the three elements, information security is sometimes described with seven elements, adding authenticity, accountability, non-repudiation and reliability.

• A. Confidentiality means only authorized people can access the information. No information was leaked here.
• B. Integrity means the information is accurate and has not been altered without authorization. Nothing was altered here.
• C. Correct. Being able to use the system when needed is availability, and that is what was lost.