220-1101 Networking Practice Test 9 — 15 Questions

Question 1

A network technician is setting up a small office with 15 workstations. The ISP provides a single public IPv4 address. The technician configures the router to assign private IP addresses (192.168.1.x) to the workstations via DHCP. Which technology allows all 15 workstations to share the single public IP address to access the internet?

Accepted Answer

NAT (Network Address Translation). NAT (Network Address Translation) allows multiple devices on a private network (like 192.168.1.x) to share a single public IPv4 address by translating the private source IP and port to the public IP and a unique port number when traffic exits the router. This enables all 15 workstations to access the internet simultaneously using the one public address provided by the ISP.

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DNS (Domain Name System)

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DHCP (Dynamic Host Configuration Protocol)

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ARP (Address Resolution Protocol)

Question 2

A technician is terminating an Ethernet cable for a 1000BASE-T network. The technician uses the T568A standard on one end and T568B on the other. Which of the following describes the resulting cable type?

Accepted Answer

Crossover. A crossover cable is created when one end is terminated with T568A and the other with T568B. In 1000BASE-T, all four pairs are used for bidirectional data transmission, and the crossover swaps the transmit and receive pairs (specifically pairs 1-2 and 3-6, and also pairs 4-5 and 7-8) to allow two like devices (e.g., two switches) to communicate directly without an uplink port.

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Straight-through

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Rollover

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Loopback

Question 3

A user in a densely populated apartment building complains of frequent Wi-Fi disconnects and slow speeds on the 2.4 GHz band. A spectrum analysis shows many overlapping networks on channels 1, 6, and 11. The router supports both 2.4 GHz and 5 GHz. Which of the following is the BEST solution to improve the user's wireless experience?

Accepted Answer

A. Change the client device to use the 5 GHz band. The 2.4 GHz band is congested with overlapping networks on channels 1, 6, and 11, causing co-channel interference and contention. Moving the client device to the 5 GHz band provides access to many more non-overlapping channels (e.g., 36, 40, 44, 48) and typically less interference, resulting in fewer disconnects and higher throughput.

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B. Change the wireless security from WPA2 to WPA3

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C. Increase the router's transmit power to maximum

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D. Change the network SSID to a unique name

Question 4

A technician is setting up a small office network with 20 computers. The ISP provides a modem that only has one Ethernet port. The technician needs to connect all computers to the internet and allow them to communicate with each other. Which device should the technician use to connect the computers to the modem?

Accepted Answer

A switch. A switch is the correct device because it operates at Layer 2 of the OSI model, using MAC addresses to forward frames only to the specific port where the destination device is connected. This allows all 20 computers to communicate with each other locally and share the single Ethernet port from the modem for internet access, while providing dedicated bandwidth per port and reducing collisions.

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A hub

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A bridge

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A router

Question 5

A small office has 12 computers connected to a single unmanaged switch, which is connected to a router providing internet access. Users report that at random times, all computers lose internet connectivity for a few seconds, then it returns. The technician observes that when the problem occurs, the lights on the switch do not change, but a Ping to the router fails. The technician has replaced the router and the switch, but the issue persists. Which of the following is the MOST likely cause?

Accepted Answer

B: A user's device acting as a rogue DHCP server. The correct answer is B because a rogue DHCP server can assign invalid IP addresses (e.g., from a different subnet or with a wrong default gateway) to clients, causing intermittent connectivity loss. When a user's device (e.g., a laptop with Internet Connection Sharing enabled or a misconfigured router) responds to DHCP DISCOVER messages faster than the legitimate router, clients receive bad configuration and lose internet access for the lease duration. The fact that the switch and router were replaced without resolution points to a device on the LAN acting as a rogue DHCP server, which is not eliminated by hardware swaps.

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A: A bad Ethernet cable between the switch and router

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C: A failing network card in one of the computers

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D: A misconfigured firewall rule on the router

Question 6

A small office network consists of a router and an unmanaged switch. Every day at 2:00 PM, users report extremely slow network performance and intermittent connectivity that lasts about 30 minutes. A technician checks the switch's interface statistics and notices a high number of CRC errors on the port connected to a VoIP phone. The cable connecting the phone to the wall jack is a known working Cat5e cable. Which of the following is the MOST likely cause of the issue?

Accepted Answer

The VoIP phone is configured for half-duplex while the switch port is using full-duplex.. A is correct because a duplex mismatch between the VoIP phone (half-duplex) and the switch port (full-duplex) causes CRC errors, collisions, and performance degradation. The daily 2:00 PM timing suggests a scheduled task like a phone firmware update or DHCP renewal that triggers heavy traffic, exacerbating the mismatch. CRC errors specifically indicate layer 1/2 frame corruption, which is a classic symptom of duplex mismatch.

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The switch is experiencing a broadcast storm caused by a loop in the network.

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The VoIP phone is running QoS that priority-tags all traffic.

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The Category 5e cable is not capable of handling VoIP traffic.

Question 7

A small office has 18 computers that need to be connected to share files and access the internet. The ISP provides a modem with a single Ethernet port. The office router has four LAN ports. Which device should the technician add to enable all 18 computers to connect to the network?

Accepted Answer

B. A switch. A switch is the correct device because it provides multiple Ethernet ports (typically 24 or 48) and operates at Layer 2, forwarding frames based on MAC addresses. This allows all 18 computers to connect to the network, share files, and access the internet through the existing router, which only has four LAN ports.

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A. A hub

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C. A bridge

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D. A firewall

Question 8

A small office network consists of a router (with built-in DHCP server) and an unmanaged switch. All 12 workstations are connected to the switch, and they have internet access. However, users cannot see each other's shared folders over the network. The technician has verified that all workstations are on the same IP subnet (192.168.1.0/24) and can ping each other successfully. Which of the following is the MOST likely cause of this issue?

Accepted Answer

The workstations are configured with different workgroup names. The correct answer is B because file and printer sharing over a Windows network requires all workstations to belong to the same workgroup (or domain) for NetBIOS-based discovery. Since the workstations can ping each other and are on the same subnet, Layer 3 connectivity is fine, but the inability to see shared folders indicates a Layer 2/application-layer name resolution issue, typically caused by mismatched workgroup names.

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The unmanaged switch is experiencing broadcast storms due to a loop

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The router's DHCP lease time is set too short

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The network cables are not properly crimped to T568B standards

Question 9

A user reports that their laptop can connect to the office Wi-Fi but cannot access any websites. The technician successfully pings the default gateway (192.168.1.1) from the laptop. The technician also logs into the router and successfully pings 8.8.8.8. Which of the following is the MOST likely cause of the issue?

Accepted Answer

The laptop's DNS settings are pointing to an invalid DNS server.. The laptop can ping the default gateway (192.168.1.1) and the router can ping 8.8.8.8, proving Layer 3 connectivity to the internet is working. However, the laptop cannot access websites, which typically indicates a DNS resolution failure. If the laptop's DNS settings point to an invalid or unreachable DNS server, it cannot resolve domain names to IP addresses, even though IP-based connectivity (like pinging 8.8.8.8) is fine.

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The laptop is configured with a static IP address outside the DHCP scope.

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The router's WAN port is disconnected.

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The ISP has a service outage affecting only web traffic.

Question 10

A technician is troubleshooting a user's workstation that can ping other computers on the local network but cannot access any websites. The user's router is configured with DHCP and DNS is set to automatic. The technician runs ipconfig /all and sees the workstation has an IP address of 192.168.1.45 with a subnet mask of 255.255.255.0 and a default gateway of 192.168.1.1. The technician successfully pings 8.8.8.8 from the workstation. Which of the following is the MOST likely cause of the issue?

Accepted Answer

The workstation has a manually configured DNS server that is unreachable. The workstation can ping 8.8.8.8 (a public IP address) successfully, which confirms that IP routing, the default gateway, and the physical network layer are all working correctly. However, it cannot access websites by name, which points to a DNS resolution failure. Since the router is set to automatic DNS but the workstation has a manually configured DNS server that is unreachable, the workstation will fail to resolve domain names into IP addresses, even though it can reach external IPs directly.

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The subnet mask is incorrect

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The network cable is faulty

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The router's DHCP server has exhausted its IP address pool

Question 11

A small office has a router serving as the DHCP and DNS server. All workstations can access the internet but cannot connect to a local file server using its hostname (\fileserver). They can successfully ping the file server's IP address (192.168.1.10). The technician has verified that the file server is powered on and sharing folders. Which of the following is the MOST likely cause of the issue?

Accepted Answer

The router's DNS server does not have a record for the file server's hostname.. The router is serving as the DNS server for the network. Since workstations can ping the file server by IP but not by hostname, the issue is that the DNS server lacks an A (or AAAA) record mapping the hostname 'fileserver' to its IP address 192.168.1.10. Without this record, name resolution fails, even though the server is reachable via IP.

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The DHCP lease on the file server has expired.

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The Windows Firewall on the file server is blocking incoming connections.

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The workstations and file server are in different workgroups.

Question 12

A small office has 15 desktop computers connected to a single managed switch. The switch is connected to a router that provides DHCP and DNS services. Users report that they can access the internet but cannot communicate with each other using computer names (e.g., \PC1). The technician verifies that all workstations are on the same subnet (192.168.1.0/24) and can successfully ping each other's IP addresses. Which of the following is the MOST likely cause of the issue?

Accepted Answer

NetBIOS over TCP/IP is disabled on the workstations. NetBIOS over TCP/IP (NBT) is required for name resolution of NetBIOS names, which are used in Windows for computer names like \PC1. When NBT is disabled, Windows cannot resolve NetBIOS names to IP addresses, preventing communication by computer name even though IP-based communication (ping) works. Since DNS is functioning (internet access works) and all computers are on the same subnet, the most likely cause is that NetBIOS over TCP/IP is disabled on the workstations.

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The DNS server is not configured correctly

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Windows Firewall is blocking file and printer sharing

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Workgroups are not configured the same on all computers

Question 13

A user at a small office reports that they can access the internet but cannot connect to the company's internal file server using its hostname (\fileserver). The user can ping the file server's IP address successfully. The technician checks the workstation's network settings and sees that it is obtaining an IP address from DHCP and the default gateway is correct. The DNS server address is set to the company's internal DNS server (192.168.1.5). Other workstations on the same network can access the file server by hostname without issue. Which of the following is the MOST likely cause of the problem?

Accepted Answer

The workstation's hosts file contains an incorrect entry for fileserver.. The user can ping the file server by IP but not by hostname, and other workstations resolve the hostname correctly. This points to a local name resolution issue on the affected workstation. The hosts file (located at %SystemRoot%\System32\drivers\etc\hosts) is checked before DNS queries, so an incorrect entry mapping 'fileserver' to a wrong or unreachable IP would cause the failure while DNS remains functional for others.

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The file server's firewall is blocking ping requests.

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The workstation's DNS cache is corrupted.

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The file server's network cable is faulty.

Question 14

A network administrator is setting up a wired network for a small office that has 25 workstations, 2 file servers, and a router with 4 LAN ports. The office uses IP-based printers and VoIP phones. The administrator wants to minimize broadcast traffic and improve network performance by separating the workstations from the servers and printers. Which of the following is the BEST solution?

Accepted Answer

Use a single managed switch and configure port-based VLANs. A managed switch with port-based VLANs allows the network administrator to logically segment the workstations from the servers and printers on the same physical switch, reducing broadcast domain size and improving performance. VLANs isolate broadcast traffic to only the ports within the same VLAN, so workstations do not see broadcasts from servers or printers, and vice versa. This solution uses a single switch, which is cost-effective and simple to manage, while meeting the requirement to minimize broadcast traffic without needing multiple routers.

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Connect all devices to a single unmanaged switch

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Connect all devices to a hub instead of a switch

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Use multiple routers to separate networks

Question 15

A user moves their laptop from a conference room to their office and connects the Ethernet cable. The laptop shows a network connection with an IP address of 169.254.22.115 and a subnet mask of 255.255.0.0. The user cannot access the internet or any network resources. Which of the following is the MOST likely cause?

Accepted Answer

The DHCP server is unreachable or failed to assign an IP address. The IP address 169.254.22.115 with a subnet mask of 255.255.0.0 is an Automatic Private IP Addressing (APIPA) address, which Windows assigns when a DHCP server is unreachable or fails to respond. Since the user moved the laptop and connected via Ethernet, the most likely cause is that the DHCP server did not assign a valid IP address, leaving the device with a link-local address that cannot route to the internet or network resources.

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The subnet mask is incorrect

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The network interface card is faulty

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The DNS server address is misconfigured