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62 multiple-choice questions and 33 flashcards on Core 1 — Networking, about 11% of the CompTIA A+ bank. Every one carries a written rationale.
Core 1 — Networking is one of 9 chapters in CoStudy's CompTIA A+ bank, and it holds 62 of the bank's 540 multiple-choice questions — roughly 11% of the total. That proportion is not arbitrary: chapters follow the certifying body's published exam outline, and the number of questions in each is set by that domain's published weight, so the share of your practice time this chapter takes matches the share of the real exam it accounts for.
Studying by chapter is worth doing once you have a diagnostic score. A single overall percentage tells you whether you are close; it does not tell you which domain is dragging. Working a weak chapter in isolation, and re-testing it in isolation, is the fastest way to move a score that has stalled — and it is why the mock exams in CoStudy report by domain rather than as one number.
10 questions drawn from this chapter, with the full rationale shown — the controlling principle behind the right answer, and why each wrong option tempts and fails.
A small business wants to move files to a hosted server with the transfer encrypted and no additional VPN. Which choice is BEST?
Answer: D — SFTP over the existing secure shell service
A) Plain FTP sends credentials and data in the clear, and anonymous access compounds the exposure. B) Telnet is unencrypted and is not a file transfer protocol at all. C) Publishing file sharing directly to the internet is a well-known high-risk practice. D) Correct — SFTP rides the SSH channel, so the transfer is encrypted end to end without any separate tunnel.
An administrator wants clients to resolve names through a filtered resolver that blocks known malicious domains. Which change accomplishes this MOST directly?
Answer: D — Point the DHCP-issued resolver addresses at the filtering service
A) Endpoint agents add protection but do not by themselves change which resolver is used. B) A browser proxy file affects browsers only and leaves other applications resolving directly. C) Blocking the resolution port outright breaks name lookups entirely rather than filtering them. D) Correct — changing the resolver addresses handed out by DHCP sends every client's lookups through the filtering service with no per-device work.
An administrator needs to manage a Linux server's command line across an untrusted network. Which protocol and port combination is MOST appropriate?
Answer: D — SSH on port 22
A) Telnet reaches a command line but transmits credentials in clear text. B) SNMP polls device metrics and does not offer an interactive shell. C) Remote desktop delivers a graphical session and is not the standard tool for a Linux shell. D) Correct — SSH on port 22 provides an encrypted command-line session, which is what an untrusted path requires.
A user complains that satellite internet feels sluggish during video calls even though speed tests show ample bandwidth. Which characteristic BEST explains this?
Answer: B — The long signal path introduces significant latency
A) Throttling would show up as reduced measured bandwidth, which is not the case. B) Correct — the round-trip distance to and from the satellite adds latency that speed tests do not capture but interactive calls expose immediately. C) Antenna gain is fixed by the hardware and affects signal quality rather than propagation delay. D) Duplex negotiation happens on the local Ethernet link and would not create call-specific lag.
A technician is documenting a wireless deployment and must record only what the current exam objectives cover about the radio layer. Which item belongs in the record?
Answer: C — The frequency bands each access point is configured to use
A) Marketing generation names change with each product cycle and are not the basis of the objectives. B) Individual lettered amendment names are no longer the framing used for this content. C) Correct — coverage is framed around the frequency bands in use together with generic wireless standards, so band configuration is the durable, testable detail. D) Vendor brand names for bonding features are proprietary and not standardized.
A remote research station has no wired infrastructure and no cellular coverage within many kilometers. Which internet connection type is MOST appropriate?
Answer: D — Satellite service using an outdoor dish
A) Fiber requires a physical build to the premises that does not exist here. B) Subscriber line service needs telephone pairs and is distance-limited from the provider equipment. C) Cable service depends on a coaxial distribution plant that is absent at a remote station. D) Correct — satellite is the practical option where no terrestrial plant of any kind reaches the site.
Which IPv6 address type is auto-configured and used for communication on the local link only?
Answer: C — Link-local (fe80::/10)
fe80::/10 link-local addresses are auto-assigned by IPv6 hosts and used for local-link communication only (not routed). Global unicast is the routable internet. ULA is private/internal routable. Multicast is one-to-many.
A technician is documenting which service uses UDP port 69 on a network device provisioning VLAN. Which service is it?
Answer: D — Trivial file transfer for device images
A) Name resolution uses port 53. B) Address leasing uses UDP 67 and 68, one port group off from the one asked about. C) Management traps arrive on UDP 162, with polling on 161. D) Correct — TFTP runs on UDP 69 and is routinely used to move firmware and configuration images to network devices.
Which statement about the 2.4 GHz band is accurate for planning a multi-access-point deployment?
Answer: A — It provides three non-overlapping channels in common use
A) Correct — the usable 2.4 GHz spectrum yields three non-overlapping channels, which constrains how densely access points can be placed. B) The 5 GHz band offers substantially more non-overlapping channels, so this reverses the relationship. C) Cordless phones, wireless peripherals and microwaves all share 2.4 GHz and cause real interference. D) Default channel widths are narrower in 2.4 GHz precisely because the band is so limited.
A SOHO user asks why their router assigns internal addresses in the 192.168.1.0 range rather than a public one. Which explanation is accurate?
Answer: B — Private ranges are non-routable and shared behind translation
A) Public addresses are not restricted to servers; the distinction is routability, not device role. B) Correct — private ranges are not routed on the internet and are shared behind a translating edge device, which conserves routable space. C) Address range has no relationship to encryption of traffic. D) Public addressing works over any medium, wired or wireless.
4 cards from the 33 in this chapter.
What is DNS?
Domain Name System — translates domain names to IP addresses (and vice versa). Hierarchy: root → TLD → authoritative servers.
What is APIPA?
Automatic Private IP Addressing — Windows assigns 169.254.x.x when DHCP fails. Allows local communication but no Internet access. A symptom of DHCP issues.
What is the role of a DHCP reservation, and how does it differ from a static IP configured on the host?
A reservation binds a specific MAC address to a fixed address in the DHCP server's scope, so the host still leases its address but always receives the same one along with current gateway, DNS, and option settings. A host-side static address bypasses DHCP entirely and must be updated manually if the network changes.
Compare the 2.4 GHz, 5 GHz, and 6 GHz wireless bands in terms of range, throughput, and interference.
2.4 GHz has the longest range and best wall penetration but the least throughput and the most interference, with only three non-overlapping channels. 5 GHz offers more channels and higher throughput at reduced range. 6 GHz adds the widest spectrum and cleanest channels with the shortest range, and only newer clients can use it.
These are a sample. The full Core 1 — Networking chapter runs 95 items with per-chapter progress tracking, on the web and in the iOS app.