CompTIA A+ Core 1 Networking Practice Exam

Level: Beginner (career changer, exam in about 4 weeks) · Questions: 30 · Suggested time: 40 minutes

Assumptions

• These are original practice questions in the style of the CompTIA A+ Core 1 networking material. They are not real exam questions. I tried to check the current exam code (I believe it's 220-1201), but my searches didn't go through. Please confirm the code on CompTIA's website. Everything tested here is basic networking that stays the same between exam versions.
• I gave extra weight to ports and protocols, since that's what you said you mix up most (11 of 30 questions). The Wi-Fi channel question uses North American (FCC) rules.
• Format: 24 multiple choice (7 of them scenarios), 4 true/false with a "why," and 2 short answer.

Instructions: Answer every question without notes, and set a 40-minute timer. For true/false, write one sentence explaining why. Finish the whole exam before you look at the answer key.

Section 1: Common Ports and Protocols

1. (Easy) What is the default port for HTTPS? A. 80 B. 443 C. 445 D. 8080

2. (Easy) A technician needs to manage a remote Linux server's command line over an encrypted connection. Which default port does this protocol use? A. 21 B. 23 C. 22 D. 25

3. (Medium) Scenario: A user can open a company web page by typing its IP address, but typing the site's name gives "server not found." Which protocol and port are most likely being blocked? A. DHCP on ports 67/68 B. LDAP on port 389 C. SNMP on ports 161/162 D. DNS on port 53

4. (Medium) A help desk tech wants to open a full graphical desktop session on a remote Windows PC using the built-in Windows tool. Which port does this need? A. 3389 B. 389 C. 5900 D. 3306

5. (Medium) A user reads email on a phone, a laptop and a tablet. They want messages and folders to stay on the server and look the same on every device. Which protocol and port should they use? A. POP3 on port 110 B. SMTP on port 25 C. IMAP on port 143 D. SMB on port 445

6. (Hard) Which pair of protocols traditionally runs over UDP and not TCP? A. SSH and Telnet B. FTP and SMB C. SMTP and POP3 D. DHCP and SNMP

7. (Hard) Which statement correctly describes FTP's two default ports? A. Port 20 carries commands; port 21 carries the file data B. Port 21 carries commands; port 20 carries data in active mode C. Ports 20 and 21 both carry encrypted file data D. Port 21 handles uploads; port 20 handles downloads

8. (Medium) Modern Windows file and printer sharing (SMB) runs directly over TCP, without NetBIOS. Which port does it use? A. 445 B. 137–139 C. 443 D. 143

9. (Easy) True or False: Telnet encrypts its session, so it's a secure replacement for SSH. Explain why.

10. (Medium) Short answer: Give the default port number for each of these:

• (a) SMTP
• (b) POP3
• (c) DHCP (server side)
• (d) HTTP

11. (Medium) Scenario: A network admin wants one monitoring tool to collect statistics from all the office switches and routers. The devices should also send alerts ("traps") when something goes wrong. Which protocol and ports fit this job? A. LDAP on port 389 B. Telnet on port 23 C. SNMP on ports 161/162 D. SMB on port 445

Section 2: Wi-Fi Standards

12. (Easy) Which IEEE standard is sold as "Wi-Fi 6"? A. 802.11n B. 802.11ac C. 802.11g D. 802.11ax

13. (Medium) Which of these standards works only in the 5 GHz band? A. 802.11ac B. 802.11n C. 802.11g D. 802.11b

14. (Hard) A customer wants to use the 6 GHz band for less crowded airwaves. Which of these was the first Wi-Fi generation to support 6 GHz? A. Wi-Fi 5 (802.11ac) B. Wi-Fi 6E C. Wi-Fi 6 (802.11ax) D. Wi-Fi 4 (802.11n)

15. (Medium) In North America, which three 2.4 GHz channels don't overlap with each other? A. 1, 5, 9 B. 36, 40, 44 C. 1, 6, 11 D. 2, 7, 12

16. (Easy) True or False: Compared with 5 GHz, the 2.4 GHz band usually reaches farther and passes through walls better, but it's more likely to have interference. Explain why.

17. (Medium) Scenario: A client lives in a crowded apartment building. Their dual-band router and laptops support Wi-Fi 5. Wi-Fi on 2.4 GHz is slow, and dozens of neighbors' networks show up. What's the best change? A. Connect the laptops to the router's 5 GHz band B. Switch the router to 802.11b/g compatibility mode C. Set the 2.4 GHz band to 40 MHz channel width D. Move the 2.4 GHz radio to channel 3

Section 3: Cable Types and Connectors

18. (Easy) Which connector goes on a standard twisted-pair Ethernet patch cable? A. RJ11 B. F-type C. LC D. RJ45

19. (Medium) A new office needs copper cabling that supports 10 Gbps across the full 100-meter run length. Which is the lowest category that meets this? A. Cat 5e B. Cat 6a C. Cat 6 D. Cat 5

20. (Medium) A cable will run through the space above a drop ceiling that's used as an air-return path for heating and cooling. What type of cable jacket do fire codes typically require there? A. Standard PVC jacket B. Direct-burial jacket C. Plenum-rated jacket D. Unshielded patch-cable jacket

21. (Medium) Two buildings on a campus are about 10 km apart and need a high-speed network link. Which cable type fits best? A. Single-mode fiber B. Multimode fiber C. Cat 6 shielded twisted pair D. RG-6 coaxial

22. (Easy) True or False: A typical home cable-internet modem connects to the wall with RG-6 coaxial cable and an F-type connector. Explain why.

23. (Hard) Scenario: An Ethernet run on a factory floor passes right next to large electric motors, and the connected PC keeps having network errors. The cable is the right length and tests fine when the motors are off. What's the best fix? A. Replace it with Cat 6 unshielded twisted pair B. Replace it with a crossover cable C. Replace it with plenum-rated UTP D. Replace it with properly grounded shielded twisted pair (STP)

Section 4: SOHO Router Setup

*24. (Easy)