CompTIA A+ · Domain 2 · 23% of the examCore 1 (220-1201) · Networking
10 practice questions. Tap an option to check it, or open “Show answer” for the explanation.
1. A help-desk technician can't connect to a user's Windows PC with Remote Desktop, and finds that the PC's firewall blocks inbound connections. Which port must be allowed?
Objective 2.1Show answerHide answer
Answer: C. TCP 3389
Remote Desktop Protocol listens on TCP 3389. Port 22 is SSH, which also gives remote command-line access but isn't what RDP uses.
Checked by Claude Opus 5.5 (high effort) · Oct 14, 2026
2. Which statement correctly describes UDP compared with TCP?
Objective 2.1Show answerHide answer
Answer: A. UDP is connectionless and doesn't acknowledge or retransmit lost data, which suits real-time voice and video
UDP has no handshake, acknowledgments or retransmission, so it has low overhead and is used for DNS queries, DHCP and VoIP. Ordered, acknowledged delivery after a three-way handshake describes TCP.
Checked by Claude Opus 5.5 (high effort) · Oct 14, 2026
3. A rural clinic is comparing internet services. Which connection type usually has the highest latency, which would make its video consultations lag?
Objective 2.7Show answerHide answer
Answer: D. Geostationary satellite
Signals to a geostationary satellite travel about 36,000 km each way, which adds roughly 600 ms of round-trip delay. DSL may have less bandwidth than other options, but its latency is low.
Checked by Claude Opus 5.5 (high effort) · Oct 14, 2026
4. A technician is installing three access points in an office that uses the 2.4 GHz band in the US. Which channels avoid overlapping interference?
Objective 2.2Show answerHide answer
Answer: B. 1, 6 and 11
In the US 2.4 GHz band, which allows channels 1 to 11, channels 1, 6 and 11 are the only set that doesn't overlap. Channel 13 isn't permitted in the US, so 3, 8 and 13 won't work. Channels 36, 40 and 44 are 5 GHz channels and can't be used by a 2.4 GHz radio.
Checked by Claude Opus 5.5 (high effort) · Oct 14, 2026
5. Which server role collects log messages from routers, switches, firewalls and servers in one central place for review?
Objective 2.3Show answerHide answer
Answer: C. Syslog server
Syslog is the standard way to send device logs to a central collector. An NTP server only keeps clocks in sync. That helps logs line up, but an NTP server doesn't store logs.
Checked by Claude Opus 5.5 (high effort) · Oct 14, 2026
6. Customers are receiving phishing emails that appear to come from your company's domain. The admin wants to publish in DNS which mail servers are allowed to send email for the domain. Which record should she create?
Objective 2.4Show answerHide answer
Answer: D. A TXT record containing an SPF policy
Sender Policy Framework is published as a TXT record listing the servers allowed to send for the domain, which receiving servers check. An MX record tells other servers where to deliver inbound mail, not who may send it.
Checked by Claude Opus 5.5 (high effort) · Oct 14, 2026
7. A network printer gets its address from DHCP, and every few weeks it gets a new IP so users can't print. The admin wants it to always get the same address while still being managed from the DHCP server. What should she configure?
Objective 2.4Show answerHide answer
Answer: A. A DHCP reservation for the printer's MAC address
A reservation ties one IP address to the printer's MAC address, so DHCP always hands it the same address. An exclusion only stops the server from handing out those addresses, so the printer would then need a manual static configuration.
Checked by Claude Opus 5.5 (high effort) · Oct 14, 2026
8. A technician must mount a new wireless access point on a ceiling with no power outlet nearby. The existing switch doesn't support PoE. What is the least expensive way to power the AP over its Ethernet cable?
Objective 2.5Show answerHide answer
Answer: C. Install a PoE injector between the switch and the AP
A PoE injector adds power to a single Ethernet run without replacing the switch. Plenum-rated cable is about fire safety in air-handling spaces and doesn't carry power on its own.
Checked by Claude Opus 5.5 (high effort) · Oct 14, 2026
9. A user's PC shows an IPv4 address of 169.254.33.10 and can't reach the internet or other hosts on the LAN. What does this indicate?
Objective 2.6Show answerHide answer
Answer: D. The PC got no response from a DHCP server and gave itself an APIPA address
Addresses in 169.254.0.0/16 come from APIPA, which Windows uses when DHCP fails. A DNS failure wouldn't change the address the PC holds; it would still have a normal DHCP-assigned address.
Checked by Claude Opus 5.5 (high effort) · Oct 14, 2026
10. In a wiring closet, a technician needs to find which of 48 unlabeled patch-panel ports connects to a particular office wall jack. Which tool should he use?
Objective 2.8Show answerHide answer
Answer: B. Toner probe
A tone generator plugged into the wall jack sends a signal along the cable, and the probe picks it up at the matching patch-panel port. A loopback plug tests whether a single port can send and receive, but it can't trace where a cable goes.
Checked by Claude Opus 5.5 (high effort) · Oct 14, 2026
Original practice questions written from CompTIA’s published exam objectives, not real exam questions. CompTIA is a trademark of CompTIA, Inc.; this site isn’t affiliated with CompTIA.