A+ Understanding Protocols Quiz

Which of the following protocols uses port 143? A. IMAP B. SMTP C. POP D. HTTPS

A (A. Correct: Internet Message Access Protocol (IMAP) uses port 143. B. Incorrect: Simple Mail Transfer Protocol (SMTP) uses port 25. C. Incorrect: Post Office Protocol (POP) uses port 110. D. Incorrect: Hypertext Transfer Protocol Secure (HTTPS) uses port 443.)

Which of the following protocols is used to receive email by a user? A. POP B. SMTP C. FTP D. RDP

A (A. Correct: Post Office Protocol (POP) is used to receive email on port 110. B. Incorrect: Simple Mail Transfer Protocol (SMTP) is used to send email on port 25. C. Incorrect: File Transfer Protocol (FTP) is used to upload and download files from a file server, and it uses port 21. D. Incorrect: Remote Desktop Protocol (RDP) is used to connect to remote systems, and it uses port 3389.)

Of the following choices, what is a difference between TCP and UDP? A. UDP provides guaranteed delivery, but TCP does not. B. TCP provides guaranteed delivery, but UDP does not. C. TCP is connection-oriented, but UDP does not use wires. D. UDP uses a three-way handshake, but TCP does not.

B (A. Incorrect: UDP does not provide guaranteed delivery, but TCP does. B. Correct: TCP provides guaranteed delivery, and UDP uses a best effort to deliver data. C. Incorrect: TCP is connection-oriented and UDP is connectionless, but this does not refer to wires. D. Incorrect: TCP uses a three-way handshake, but UDP does not.)

What service provides the IP address of a computer when queried with the name of the computer? A. FTP B. SMTP C. DNS D. SSL

C (A. Incorrect: File Transfer Protocol (FTP) is used to upload and download files to and from an FTP server. B. Incorrect: Simple Mail Transfer Protocol (SMTP) is used to send email. C. Correct: Domain Name System (DNS) maps computer names to IP addresses and answers name resolution requests. D. Incorrect: Secure Sockets Layer (SSL) is used to encrypt HTTPS, and it uses port 443.)

Which of the following are the correct ports for HTTP and HTTPS? A. 22 and 25 B. 80 and 143 C. 80 and 443 D. 443 and 3389

C (A. Incorrect: Secure Shell (SSH) uses port 22, and Simple Mail Transfer Protocol (SMTP) uses port 25. B. Incorrect: HTTP uses port 80, but Internet Message Access Protocol (IMAP) uses port 143. C. Correct: Hypertext Transfer Protocol (HTTP) uses port 80; Hypertext Transfer Protocol Secure (HTTPS) uses port 443. D. Incorrect: HTTPS uses port 443, but Remote Desktop Protocol (RDP) uses port 3389.)

What protocol could you use to encrypt FTP traffic? A. HTTPS B. TFTP C. RDP D. SSH

D (A. Incorrect: Hypertext Transfer Protocol Secure (HTTPS) secures webpages but not FTP traffic. B. Incorrect: Trivial File Transfer Protocol (FTP) is a scaled down version of FTP, but it does not encrypt FTP. C. Incorrect: The Remote Desktop Protocol (RDP) is used to connect to remote systems, but it does not encrypt FTP. D. Correct: Secure Shell (SSH) can be used to encrypt network traffic including File Transfer Protocol (FTP) traffic.)

You are troubleshooting an email problem for a user. The mail server is named mail, and you suspect that it is not answering SMTP queries. Which of the following commands can you use from the command prompt to test it? A. SMTP mail 23 B. SMTP mail 25 C. Telnet mail 23 D. Telnet mail 25

D (A. Incorrect: There is no such command as SMTP. B. Incorrect: There is no such command as SMTP. C. Incorrect: This command will check to see whether Telnet was running on the mail server, because it is using port 23. D. Correct: The telnet command can connect to a server on specific ports. You want to check the mail server, so you should check the SMTP service on port 25.)

What port should be opened on a firewall to allow a user to connect to a system using RDP? A. 69 B. 143 C. 443 D. 3389

D (A. Incorrect: Trivial File Transfer Protocol (TFTP) uses port 69 and is unrelated to RDP. B. Incorrect: Internet Message Access Protocol (IMAP) uses port 143 and is unrelated to RDP. C. Incorrect: Hypertext Transfer Protocol Secure (HTTPS) uses port 443 and is unrelated to RDP. D. Correct: Remote Desktop Protocol (RDP) uses port 3389, so this port needs to be opened on the firewall.)