To ensure the security of sensitive data, which protocol is best avoided?

The best protocol to avoid for securing sensitive data is PAP, or Password Authentication Protocol. PAP is a simple authentication protocol that transmits user credentials, such as usernames and passwords, in clear text without any encryption. This means that if the data is intercepted during transmission, attackers can easily read the credentials, compromising the security of the sensitive data.

In contrast, the other protocols listed—SSH, CHAP, and SSL—offer stronger security measures. SSH (Secure Shell) provides encrypted communications over a network, making it far superior for safeguarding sensitive information. CHAP (Challenge Handshake Authentication Protocol) enhances security by using a challenge-response mechanism to verify credentials without sending them in clear text. SSL (Secure Sockets Layer) also secures communications between web servers and clients by encrypting the data transmitted across the network.

Therefore, it is crucial to avoid using PAP in environments where security is a priority, as it does not provide any mechanism to protect against eavesdropping or data theft.