CompTIA Network+ Certification (N10-003) Part 11

1. Which of the following uses ports 20 and 21?

FTP

TFTP

IMAP4

NTP

FTP uses TCP port 20 for data and TCP port 21 for control.

Explanation

FTP uses TCP port 20 for data and TCP port 21 for control.

2. Which port must you close on a firewall to prevent users from browsing the Internet?

21

25

80

110

HTTP transmits data between a web browser and the Internet. HTTP uses TCP port 80. Thus, closing TCP port 80 will prevent users from accessing the Internet.

Explanation

HTTP transmits data between a web browser and the Internet. HTTP uses TCP port 80. Thus, closing TCP port 80 will prevent users from accessing the Internet.

3. Which of the following uses port 22?

Telnet

Secure Shell

HTTP

HTTPS

Secure Shell (SSH) uses TCP port 22.

Explanation

Secure Shell (SSH) uses TCP port 22.

4. What is the default TCP port used by HTTP?

21

23

80

443

The default port for HTTP is TCP port 80.

Explanation

The default port for HTTP is TCP port 80.

5. Which of the following uses port 443?

Telnet

HTTP

IMAP4

HTTPS

HTTPS uses TCP port 443.

Explanation

HTTPS uses TCP port 443.

6. You are working as a network technician. A developer wants to know what is the default port that listens to the URL https://www.google.com. How do you answer?

21

23

80

110

Web browsers use HTTP to access web sites. The default port for HTTP is TCP port 80.

Explanation

Web browsers use HTTP to access web sites. The default port for HTTP is TCP port 80.

7. Which of the following provides name resolution on the Internet?

Dynamic Host Configuration Protocol (DHCP)

Domain Name Services (DNS)

Windows Internet Name Service (WINS)

Network Address Translation (NAT)

The Internet uses host names and DNS is responsible for host name resolution.

Explanation

The Internet uses host names and DNS is responsible for host name resolution.

8. Which ports must you open on a firewall to allow FTP traffic? (choose all that apply)

20

21

23

25

FTP uses TCP port 20 for data and TCP port 21 for control.

Explanation

FTP uses TCP port 20 for data and TCP port 21 for control.

Submit

9. SMTP is identified by which of the following well-known TCP/IP ports?

21

23

25

110

TCP port 25 is the default port SMTP

Explanation

TCP port 25 is the default port SMTP

10. You work as a network technician. You are asked to troubleshoot a problem where a user is unable to connect to a File Transfer Protocol (FTP) server even if port 21 is unblocked on the corporate firewall. What is the most probable cause of this problem?

Trivial File Transfer Protocol (TFTP) is not installed

Network File System (NFS) is not installed

Port 20 must also be unlocked

Port 22 must also be unlocked

FTP uses both TCP port 21 and port 22. TCP port 21 is used for control while TCP port 20 is used for data. Therefore, you should unblock both port 20 and 21.

Explanation

FTP uses both TCP port 21 and port 22. TCP port 21 is used for control while TCP port 20 is used for data. Therefore, you should unblock both port 20 and 21.

11. What is the default TCP port used by HTTPS?

21

23

80

443

The default port for HTTPS is TCP port 443.

Explanation

The default port for HTTPS is TCP port 443.

12. You want to determine which IP address www.google.com resolves to. Which of the following types of servers is required to accomplish this?

Dynamic Host Configuration Protocol (DHCP)

Domain Name Services (DNS)

Windows Internet Name Service (WINS)

Network Address Translation (NAT)

DNS is responsible for resolving host names like www.google.com to an IP address.

Explanation

DNS is responsible for resolving host names like www.google.com to an IP address.

13. Which of the following uses port 23?

Telnet

Secure Shell

HTTP

HTTPS

Telnet uses TCP port 23.

Explanation

Telnet uses TCP port 23.

14. Which of the following provides NetBIOS name to IP address resolution?

Dynamic Host Configuration Protocol (DHCP)

Domain Name Services (DNS)

Windows Internet Name Service (WINS)

Network Address Translation (NAT)

WINS provides NetBIOS name to IP address resolution.

Explanation

WINS provides NetBIOS name to IP address resolution.

15. Which of the following uses port 143?

Telnet

HTTP

IMAP4

HTTPS

IMAP4 uses TCP port 143.

Explanation

IMAP4 uses TCP port 143.

16. Which of the following ports is required by Secure Shell?

20

21

22

23

Secure Shell (SSH) uses TCP port 22.

Explanation

Secure Shell (SSH) uses TCP port 22.

17. You work as a network administrator and you've been asked to configure a Microsoft Exchange server for e-mail services at a branch office. The Exchange server has to be able to send e-mail to the main office that uses a Novel GroupWise e-mail server. What protocol is needed to send e-mail between the two servers?

Client Service for Netware (CSNW)

Simple Mail Transfer Protocol (SMTP)

Internet Packet Exchange / Sequence Packet Exchange (IPX/SPX)

Post Office Protocol version 3 (POP3)

Simple Mail Transfer Protocol (SMTP) is used for transfering e-mail messages between servers.

Explanation

Simple Mail Transfer Protocol (SMTP) is used for transfering e-mail messages between servers.

18. Which of the following ports should be allowed to pass the corporate firewall to allow a remote user to log onto a corporate server using the SSH terminal from home?

23

22

21

20

SSH uses TCP port 22. Therefore, this port should be redirected from the router to the IP address to allow SSH terminal connectivty.

Explanation

SSH uses TCP port 22. Therefore, this port should be redirected from the router to the IP address to allow SSH terminal connectivty.

19. When using a modem for dial-up networking in Windows which of the following protocols is normally used to establish the connection?

Hypertext Transfer Protocol (HTTP)

Telnet

Point-to-Point Protocol (PPP)

Secure Shell (SSH)

The PPP protocol is used to establish a connection over point-to-point links such as dial-up and dedicated leased lines.

Explanation

The PPP protocol is used to establish a connection over point-to-point links such as dial-up and dedicated leased lines.

20. You are a senior network technician. A trainee asks you which of the following protocols is used for error reporting in IP. How do you answer?

SMTP

ICMP

IGMP

SNMP

Internet Control Message Protocol (ICMP) is used for network management and control. It provides error testing and reporting for TCP/IP.

Explanation

Internet Control Message Protocol (ICMP) is used for network management and control. It provides error testing and reporting for TCP/IP.

21. Which of the following cannot be used for remote connections?

Telnet

SSH

PPP

IMAP4

IMAP4 transmit e-mail between the e-mail client and the e-mail server. This does not allow remote connections.

Explanation

IMAP4 transmit e-mail between the e-mail client and the e-mail server. This does not allow remote connections.

22. Which ports must you open on a firewall to allow e-mail communications? (choose all that apply)

21

25

80

110

TCP port 25 is used by SMTP which transmits e-mail from one server to another. TCP port 110 is used by POP3 to transmit e-mail betwen server and clients.

Explanation

TCP port 25 is used by SMTP which transmits e-mail from one server to another. TCP port 110 is used by POP3 to transmit e-mail betwen server and clients.

Submit

23. Which of the following provides HOST name to IP address resolution?

Dynamic Host Configuration Protocol (DHCP)

Domain Name Services (DNS)

Windows Internet Name Service (WINS)

Network Address Translation (NAT)

DNS provides host name to IP address resolution.

Explanation

DNS provides host name to IP address resolution.

24. You are a network technician. Your boss asks if it is possible to encrypt data between web browser and web server. You answer that it is possible but it requires the use of ______.

IPSec

SSL

PPTP

L2TP

Secure Socket Layer (SSL) provides secure Session Layer connections over the Internet between a web browser and web server.

Explanation

Secure Socket Layer (SSL) provides secure Session Layer connections over the Internet between a web browser and web server.

25. Which of the following ports allow secure HTTP traffic?

22

80

143

443

HTTPS provides secure HTTP traffic uses TCP port 443 and not TCP port 80.

Explanation

HTTPS provides secure HTTP traffic uses TCP port 443 and not TCP port 80.

26. Which of the following network services provides name resolution? (choose all that apply)

Dynamic Host Configuration Protocol (DHCP)

Domain Name Services (DNS)

Windows Internet Name Service (WINS)

Network Address Translation (NAT)

DNS provides host name to IP address resolution while WINS provides NetBIOS name to IP address resolution.

Explanation

DNS provides host name to IP address resolution while WINS provides NetBIOS name to IP address resolution.

Submit

27. You work as a network engineer. You have been asked to verify that the Simple Mail Transfer Protocol (SMTP) service is running on a remote server in a branch office. The server does not allow Remote Desktop connections. You know that you can test the SMTP port with telnet but on what port number should you establish the session?

20

21

23

25

To check if SMTP is running test port 25.

Explanation

To check if SMTP is running test port 25.

28. You work as a network administrator and you have been asked to setup a new mail server in a new domain on your network. Which DNS records would you request to be created before e-mail can be received from the Internet to the new e-mail server?

Address (A) record only

Mail Exchanger (MX) records only

Mail Exchanger (MX) and Canonical Name (CNAME) records

Mail Exchanger (MX) and Address (A) records

The MX record points to the mail exchanger for a particular host. This ensures that e-mail for a particular host will go to the correct mail exchanger. However, e-mail addresses use host names but computers use IP addresses. Therefore, we also need to translate host names to IP addresses. The Address (A) record maps a host name to an IP address.

Explanation

The MX record points to the mail exchanger for a particular host. This ensures that e-mail for a particular host will go to the correct mail exchanger. However, e-mail addresses use host names but computers use IP addresses. Therefore, we also need to translate host names to IP addresses. The Address (A) record maps a host name to an IP address.

29. You are working as a senior network technician. One of your trainees has some questions about name resolution. He says he knows about DNS name resolution but wonders what is required in order to resolve Network Basic Input/Output System (NetBIOS) name to Internet Protocol (IP) address resolution. How would you answer?

Ipconfig

LMHOSTS

Domain Name Services (DNS)

Dynamic Host Configuration Protocol (DHCP)

LMHOSTS and WINS provides NetBIOS name to IP address resolution.

Explanation

LMHOSTS and WINS provides NetBIOS name to IP address resolution.

30. Which of the following provides remote logon over the Internet?

Telnet

SSH

PPP

IMAP4

The PPP protocol is used to establish a connection over point-to-point links such as dial-up and dedicated leased lines that are used to connect to the Internet.

Explanation

The PPP protocol is used to establish a connection over point-to-point links such as dial-up and dedicated leased lines that are used to connect to the Internet.