Certified Information Systems Security Professional (CISSP) — Question 233

Which of the following secure transport protocols is often used to secure Voice over Internet Protocol (VoIP) communications on a network from end to end?

Answer options

• A. Secure File Transfer Protocol (SFTP)
• B. Secure Real-time Transport Protocol (SRTP)
• C. Generic Routing Encapsulation (GRE)
• D. Internet Protocol Security (IPSec)

Correct answer: B

Explanation

The correct answer is B, Secure Real-time Transport Protocol (SRTP), which is specifically designed to provide encryption, message authentication, and integrity, making it ideal for VoIP communications. The other options, such as SFTP, are not focused on real-time communication, while GRE and IPSec serve different purposes in the realm of networking and security.