ISA/IEC 62443 Cybersecurity Fundamentals Specialist — Question 23

Which layer in the Open Systems Interconnection (OSI) model would include the use of the File Transfer Protocol (FTP)?

Answer options

• A. Application layer
• B. Data link layer
• C. Session layer
• D. Transport layer

Correct answer: A

Explanation

The correct answer is A, as the Application layer is responsible for network services that applications use, including FTP for file transfers. The Data link layer (B) handles node-to-node data transfer, the Session layer (C) manages sessions, and the Transport layer (D) ensures complete data transfer but does not include application-specific protocols like FTP.