CompTIA Network+ (N10-009) practice questions
218 free questions with answers and explanations.
- 101.A penetration tester connects a laptop to an access port and successfully sends traffic to a VLAN it should not have access to by crafting frames with two 802.1Q tags. Which attack technique was used?Network Security
- 102.A technician configures a web server to encrypt all client-browser traffic using TLS. Which well-known port does the server use to accept these secure HTTP connections?Networking Concepts
- 103.A network technician is explaining to a junior colleague how a client obtains an IP address from a DHCP server. Which sequence correctly describes this process?Network Operations
- 104.A vendor notifies a company that a firewall model has reached end-of-support (EOS), though the hardware remains functional and installed in production. What is the primary risk this status introduces?Network Operations
- 105.A user in a branch office can reach servers on the local subnet but cannot access any resources outside the subnet, including the internet. The user's IP configuration shows an address of 192.168.10.55/24 and a default gateway of 192.168.11.1. What is the MOST likely cause of this issue?Network Troubleshooting
- 106.A network engineer is configuring a site-to-site VPN between two offices and must decide how the original IP packet will be protected. The design requires that the entire original IP packet, including its header, be encrypted and encapsulated inside a new IP packet for transport across the internet. Which IPsec mode should be configured?Network Operations
- 107.A company needs to host a public-facing web server that is reachable from the internet while ensuring that a compromise of that server does not give an attacker direct access to the internal LAN. Which architecture should be implemented?Network Security
- 108.A technician needs to connect two buildings located 2 kilometers apart using fiber optic cable, with no repeaters or amplifiers along the run. Which cable type should be selected?Network Implementation
- 109.A network administrator is investigating reports of intermittent connectivity and slow speeds on the 5 GHz Wi-Fi network in a dense office environment. A Wi-Fi analyzer shows multiple access points (APs) from neighboring organizations broadcasting on overlapping channels, along with high levels of interference from non-Wi-Fi sources. Which of the following would be the MOST effective solution to improve performance and stability?Network Troubleshooting
- 110.A company recently added several new VoIP phones and Wi-Fi access points to a PoE switch that already powers existing devices. Shortly afterward, some devices begin randomly losing power and rebooting, especially during peak usage. Cable testing shows no faults. What is the most likely cause?Network Troubleshooting
- 111.A technician connects two switches directly together using a standard Ethernet patch cable instead of a crossover cable, and the link comes up successfully with no manual configuration. Which feature on modern switch ports allows this to work?Network Implementation
- 112.A network technician is configuring a switch trunk link that will carry traffic for VLANs 10, 20, and 30 between two switches. Which protocol should the technician enable on the trunk port to tag frames with their VLAN membership as they cross the link?Network Implementation
- 113.A network architect is implementing a software-defined networking (SDN) solution and explains to stakeholders that a centralized controller will make all forwarding decisions and push instructions to switches, which will simply execute those instructions on incoming traffic. Which architectural concept does this describe?Networking Concepts
- 114.A company keeps sensitive financial records on private, on-premises servers but wants to leverage a public cloud provider's elastic compute resources during seasonal traffic spikes for its public-facing website. Which cloud deployment model best fits this requirement?Networking Concepts
- 115.A wireless engineer is designing a network and must choose between deploying access points primarily on the 2.4GHz band versus the 5GHz band. Which statement correctly describes the tradeoff?Network Implementation
- 116.A network engineer assigns a workstation the IPv6 address 2001:0db8:85a3:0000:0000:8a2e:0370:7334, which is routable across the internet and assigned by the organization's ISP. What type of IPv6 address is this?Networking Concepts
- 117.A network administrator is performing a routine check of network devices. When attempting to log into a managed switch via SSH, the connection attempt consistently times out. Pinging the switch's management IP address is successful. Other services on the switch, such as SNMP, are also responding. Which of the following is the MOST likely cause of the SSH timeout?Network Troubleshooting
- 118.A DHCP server issues a lease with a total lease time of 8 hours. According to standard DHCP renewal timer behavior, at approximately what point into the lease will the client first attempt to renew its lease directly with the original DHCP server (T1 timer)?Network Operations
- 119.A web server hosting company notices a sudden flood of SYN packets from thousands of distinct source IP addresses, all targeting a single customer's server and exhausting its connection table. Which type of attack is this?Network Security
- 120.An attacker sets up a wireless access point in a coffee shop using the same SSID as the legitimate shop Wi-Fi, hoping customers will connect to it instead. Which attack is being described?Network Security
- 121.A network administrator wants VLAN 10 traffic to use SwitchA as the spanning tree root bridge while VLAN 20 traffic uses SwitchB as the root bridge, allowing traffic load to be balanced across both uplinks. Which switching technology natively supports this per-VLAN root bridge assignment?Network Implementation
- 122.A security policy states that patient billing records must remain unaltered during transmission between a clinic's EHR system and its billing vendor. Which tenet of the CIA triad does this requirement primarily address?Network Security
- 123.A network administrator has a primary route to the 10.20.0.0/16 network learned via OSPF. The administrator wants to configure a backup static route through a secondary ISP that will only be used if the OSPF route becomes unavailable. What administrative distance should be assigned to the static route?Network Implementation
- 124.A company wants to ensure that any device connecting to its network first has up-to-date antivirus definitions and OS patches before being granted full network access. Which technology should be implemented?Network Security
- 125.A company is running fiber optic cable between two buildings located 8km apart on the same campus. Which fiber type is best suited for this long-distance run?Networking Concepts
- 126.A network administrator is creating documentation that shows VLAN assignments, IP subnets, and routing paths between sites, but does not include physical cable runs or rack locations. Which type of diagram is being created?Network Operations
- 127.A company wants remote employees working from home to securely access internal file servers over the public internet as if they were directly connected to the corporate LAN, with all traffic encrypted end-to-end. Which technology best meets this requirement?Networking Concepts
- 128.A network administrator needs to distribute incoming web traffic across three identical backend servers to prevent any single server from becoming overwhelmed. Which appliance should be deployed?Networking Concepts
- 129.Several new employees at a branch office report that their laptops receive IP addresses in the 169.254.0.0/16 range and cannot access any network resources. Other existing devices on the same subnet are functioning normally. What is the MOST likely cause?Network Troubleshooting
- 130.A data center architect is designing a new fabric where every leaf switch connects to every spine switch, but leaf switches do not connect directly to each other, ensuring predictable low-latency paths for east-west traffic between servers. Which topology is being implemented?Networking Concepts
- 131.A technician terminates a Cat 6 patch cable and later finds that a workstation connected to it cannot establish a link light, while other cables on the same run work fine. Using a cable tester, the technician sees that pins 1 and 2 show no continuity on one end. Which cabling issue does this indicate?Network Troubleshooting
- 132.A technician is troubleshooting a client device that cannot synchronize its clock with the internal NTP server. Firewall logs show the synchronization attempts being blocked. Which port and protocol combination should the technician permit to allow NTP traffic?Network Operations
- 133.At which layer of the OSI model does a switch primarily operate when forwarding frames based on MAC addresses?Networking Concepts
- 134.A company is deploying a SIP-based VoIP service and wants client devices to automatically discover the correct server hostname and port for SIP signaling over TCP. Which DNS record type should be published to support this automatic discovery?Network Operations
- 135.Users on a subnet report intermittent connectivity issues, and a technician discovers that a workstation is broadcasting gratuitous ARP replies claiming to own the default gateway's IP address. Which mitigation, when configured on the switch, would have BEST prevented this?Network Security
- 136.A technician is installing a Cat 6 UTP horizontal cable run from a telecommunications closet to a workstation. The measured cable length is 105 meters. Which issue is MOST likely to occur as a result?Network Implementation
- 137.A penetration tester crafts an Ethernet frame containing two nested 802.1Q VLAN tags and sends it from a host on the native VLAN of a trunk link. The goal is to have the frame processed on a VLAN the host should not have access to. Which attack is being demonstrated?Network Implementation
- 138.A growing organization struggles to track which IP addresses are assigned, reserved, or available across multiple subnets and DHCP scopes. Which type of tool would best solve this problem?Network Operations
- 139.An access point has a transmitter power output of 20 dBm. The signal passes through a cable with 2 dB of loss before reaching an antenna with 6 dBi of gain. What is the resulting Effective Isotropic Radiated Power (EIRP)?Network Implementation
- 140.A network administrator configures a router so that any traffic not matching a more specific entry in the routing table is forwarded to the ISP's gateway. Which type of route accomplishes this?Network Implementation
- 141.A technician wants to determine the likely operating system running on several unidentified hosts on the network without needing valid login credentials. Which nmap option is designed for this purpose?Network Troubleshooting
- 142.A technician is troubleshooting a total loss of internet connectivity at a small office. After testing, the ISP confirms that the circuit is functioning correctly up to the point where their cabling terminates and the customer's equipment begins. Which term describes this boundary?Network Implementation
- 143.A data center administrator notices most traffic flows between servers within the same data center (server-to-server) rather than between clients outside the data center and servers inside it. How is this internal server-to-server traffic pattern classified?Networking Concepts
- 144.An ISP allocates a customer the IPv6 prefix 2001:db8:1234:5670::/60. The network administrator plans to create separate /64 subnets for each VLAN within this allocation. How many /64 subnets are available?Networking Concepts
- 145.A development team wants to build and deploy custom applications on a vendor-managed platform that provides the operating system, runtime, and middleware, so the team only needs to focus on writing and managing application code. Which cloud service model best fits this need?Networking Concepts
- 146.A security team wants a network appliance that actively blocks malicious traffic in real time by sitting inline with the traffic flow, rather than only alerting administrators after detecting an attack. Which device should be deployed?Networking Concepts
- 147.A vendor datasheet for a switch lists a Mean Time Between Failures (MTBF) of 100,000 hours and a Mean Time To Repair (MTTR) of 4 hours. Using the standard availability formula, what is the calculated availability of this device?Network Operations
- 148.Users report that internal web application URLs resolve to an old server's IP address even after the application was migrated to a new server three days ago. Other websites resolve correctly. Which action would MOST likely resolve this issue?Network Troubleshooting
- 149.Before installing wireless access points in a newly leased warehouse, a wireless engineer walks the entire facility with specialized software and a mobile device to measure signal strength, identify sources of interference, and map coverage gaps. What is this process called?Network Implementation
- 150.A network administrator wants each switch access port to learn only one MAC address automatically and to disable the port if a second, unauthorized device is detected. Which configuration accomplishes this?Network Security