220-1101 Networking Practice Test 9 — 15 Questions

Question 1

A user installs a new third-party security software suite on their Windows workstation. After installation, the user can still access files on the local network and can ping external IP addresses like 8.8.8.8, but cannot browse any websites using a web browser. Other workstations on the same network are unaffected. Which of the following is the MOST likely cause?

Choose an answer to begin — your selection is scored in the full session.

Accepted Answer

The security software's firewall is blocking outbound HTTP/HTTPS traffic. The user can ping external IP addresses (e.g., 8.8.8.8) and access local network files, which confirms that IP connectivity, the default gateway, and DNS resolution for local resources are working. However, the inability to browse websites (which use HTTP/HTTPS) while other workstations are unaffected strongly indicates that the new third-party security software's firewall is blocking outbound TCP ports 80 and 443. This is a common behavior of security suites that enable strict outbound filtering by default.

Answer

The DNS server address was changed by the software

Answer

The workstation's default gateway was removed

Answer

The security software corrupted the browser's configuration files

Question 2

A technician is configuring a small office network with a managed switch and a router that supports inter-VLAN routing. A workstation on VLAN 10 (192.168.10.0/24) can ping other workstations on VLAN 10 but cannot ping a server on VLAN 20 (192.168.20.0/24). The switch has a trunk port connecting to the router, and the trunk is configured to allow VLANs 10 and 20. The workstation's default gateway is set to 192.168.10.1. The server's default gateway is set to 192.168.20.1. Which of the following is the MOST likely cause of the problem?

Accepted Answer

A. The router's subinterface for VLAN 20 is not configured or is incorrectly configured.. The workstation can communicate within VLAN 10 but cannot reach VLAN 20, indicating that inter-VLAN routing is failing. Since the trunk is correctly allowing VLANs 10 and 20, the most likely cause is that the router's subinterface for VLAN 20 (e.g., GigabitEthernet0/0.20) is missing, has an incorrect encapsulation dot1Q 20 command, or lacks an IP address in the 192.168.20.0/24 subnet. Without a properly configured subinterface, the router cannot route traffic to or from VLAN 20.

Answer

B. The workstation's firewall is blocking ICMP echo requests.

Answer

C. The switch port connecting the router is configured as an access port on VLAN 1.

Answer

D. The server's default gateway is set to 192.168.20.254.

Question 3

A technician configures a new workstation with DHCP. Initially, the workstation obtains an IP address of 192.168.1.100/24 with default gateway 192.168.1.1 and can browse the internet. After approximately 30 minutes, the user reports that internet access stops working, but the workstation can still ping other local devices on the same subnet. The technician runs ipconfig and sees that the workstation now has an IP address of 169.254.15.78. Which of the following is the MOST likely cause?

Accepted Answer

The DHCP lease expired and the workstation could not contact the DHCP server to renew it. The workstation initially received a valid DHCP lease (192.168.1.100/24). After 30 minutes, the lease expired, and the workstation failed to renew it from the DHCP server. As a result, Windows Automatic Private IP Addressing (APIPA) assigned a 169.254.x.x address, which allows local subnet communication but not internet access. This matches the symptom of losing internet while retaining local connectivity.

Answer

The DHCP server has run out of available IP addresses in the scope

Answer

The DNS server address provided by DHCP has become invalid

Answer

The switch port the workstation is connected to was moved to a different VLAN without trunking

Question 4

Employees in a small office report that their wired network connections become extremely slow or drop every time the office microwave oven is used. The microwave is located in the breakroom, and the network cables for the cubicles run through the ceiling directly above the breakroom. The cables currently installed are unshielded twisted pair (UTP) Cat5e. The technician has confirmed the microwave is not physically damaging the cables and that the router and switch are not overheating. Which of the following solutions would MOST effectively resolve the intermittent network issues?

Accepted Answer

Replace the UTP Cat5e cables with STP Cat6a cables. The intermittent network slowdowns and drops are caused by electromagnetic interference (EMI) generated by the microwave oven, which radiates strongly in the 2.4 GHz range. UTP Cat5e cables lack shielding and are susceptible to this EMI, especially when running through the ceiling directly above the microwave. Replacing them with STP Cat6a cables provides foil or braided shielding that blocks EMI, preserving signal integrity and resolving the issue.

Answer

Upgrade the network switches to models that support QoS (Quality of Service)

Answer

Install ferrite chokes on both ends of each network cable

Answer

Replace the RJ45 wall jacks with shielded Cat6 jacks

Question 5

A small office network uses a single router configured as a DHCP server for the 192.168.1.0/24 network. The DHCP scope is set to 192.168.1.10 - 192.168.1.50. Over the past week, several workstations have reported intermittent connectivity. The technician checks a workstation and finds that its IP address has changed from 192.168.1.20 to 169.254.15.100. Other workstations also show similar APIPA addresses. The DHCP server logs indicate that many lease requests are being declined. The network has 45 devices that require IP addresses. Which of the following is the MOST likely cause of the issue?

Accepted Answer

The DHCP scope is too small for the number of devices on the network. The DHCP scope is 192.168.1.10–192.168.1.50, which provides only 41 usable addresses. With 45 devices requiring IP addresses, the scope is exhausted. When a DHCP server cannot assign an address, clients self-assign an APIPA address (169.254.x.x) per RFC 3927, explaining the intermittent connectivity and declined lease requests.

Answer

The DHCP server is malfunctioning and needs to be restarted

Answer

The DNS server is not resolving hostnames correctly

Answer

The network switch is flooding the network with broadcast traffic

Question 6

A user can access local network resources but cannot browse the internet. Other users on the same network have no issues. The technician checks the workstation's IP configuration: IP 192.168.1.100, subnet mask 255.255.255.0, default gateway 192.168.1.1, DNS server 192.168.1.1. The workstation successfully pings the default gateway (192.168.1.1). The technician then tries to ping 8.8.8.8 and the ping fails. Which of the following should the technician check NEXT?

Accepted Answer

The routing table on the router. Since the workstation can ping the default gateway (192.168.1.1) but cannot ping 8.8.8.8, the issue is beyond the local subnet. This indicates a routing problem, not a local connectivity or DNS issue. The technician should check the router's routing table to ensure there is a default route (0.0.0.0/0) pointing to the ISP or upstream gateway, as the router may not be forwarding traffic to external networks.

Answer

The switch port configuration

Answer

The DNS server settings

Answer

The DHCP lease expiration

Question 7

A user reports that they cannot access the internet, but they can still access shared folders on the local network. The technician runs ipconfig on the workstation and sees an IP address of 169.254.10.15 with a subnet mask of 255.255.0.0. Which of the following is the MOST likely cause of this issue?

Accepted Answer

The DHCP server is unavailable. The IP address 169.254.10.15 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 unavailable or fails to respond. Since the user can still access local shared folders (local link-layer communication works), but cannot reach the internet, the core issue is the lack of a valid DHCP lease, not a DNS or gateway misconfiguration.

Answer

The DNS server is not responding

Answer

The default gateway address is incorrect

Answer

The workstation has a static IP address configured

Question 8

A user reports that they cannot access any websites using their web browser, but they can successfully ping external IP addresses such as 8.8.8.8. Other users on the same network are able to browse the internet normally. The technician checks the workstation's IP configuration and finds the following: IP 192.168.1.50, subnet mask 255.255.255.0, default gateway 192.168.1.1, DNS server 192.168.1.1. The technician can ping 192.168.1.1 successfully. Which of the following is the MOST likely cause?

Accepted Answer

DNS server not responding or misconfigured. The user can ping external IP addresses (e.g., 8.8.8.8) and the default gateway (192.168.1.1), confirming that IP routing and the gateway are functional. However, they cannot resolve domain names to IP addresses, which is a classic symptom of DNS failure. Since the DNS server is set to 192.168.1.1 (likely the gateway) and other users on the same network can browse normally, the issue is isolated to this workstation's DNS configuration or the DNS service on that server not responding to this specific client.

Answer

Incorrect subnet mask

Answer

Incorrect default gateway

Answer

Firewall blocking web traffic (port 80/443)

Question 9

A company replaces an unmanaged network switch with a new managed switch in a small office. After reconnecting all devices, some workstations can access the internet, but others cannot. The workstations that cannot access the internet are all connected to ports 1-8 of the new switch, while workstations on ports 9-16 work normally. The router is connected to port 24. The technician checks the switch configuration and finds that all ports are in the default VLAN 1, but ports 1-8 have been accidentally reassigned to VLAN 2. Which of the following is the MOST likely reason the workstations on ports 1-8 cannot access the internet?

Accepted Answer

The workstations on ports 1-8 are on a different VLAN than the router, preventing them from reaching the default gateway.. The router is connected to port 24, which remains in the default VLAN 1. Workstations on ports 1-8 have been reassigned to VLAN 2. Since VLANs create separate broadcast domains, devices in VLAN 2 cannot communicate with the router's interface in VLAN 1 unless a Layer 3 device (like a router or Layer 3 switch) routes between the VLANs. Without inter-VLAN routing configured, the workstations in VLAN 2 cannot reach their default gateway (the router), and thus cannot access the internet.

Answer

The switch needs to be power cycled to apply the VLAN configuration changes.

Answer

The workstations on ports 1-8 have incorrect subnet masks configured.

Answer

The switch ports are not configured as trunk ports for the router connection.

Question 10

A small office uses a single router as the DHCP server for the 192.168.1.0/24 network. The DHCP scope is configured to issue addresses from 192.168.1.100 to 192.168.1.200. A new employee connects a laptop to an available wall jack and receives an IP address of 169.254.13.57. Other devices in the office are receiving valid IP addresses in the 192.168.1.x range. The technician checks the wall jack and the switch port, and the link light is solid green. Which of the following is the MOST likely cause of this issue?

Accepted Answer

The switch port is configured for a VLAN that does not have access to the DHCP server. The APIPA address 169.254.13.57 indicates the laptop failed to receive a DHCP lease. Since other devices on the same network are getting valid 192.168.1.x addresses, the DHCP server is functional and the scope is not exhausted. A solid link light confirms Layer 1 connectivity, so the most likely cause is that the switch port is assigned to a VLAN that does not have Layer 3 access to the DHCP server, preventing the DHCP discover/offer handshake from completing.

Answer

The laptop's network adapter is faulty

Answer

The DHCP scope is exhausted

Answer

The router's DHCP service is disabled

Question 11

A network technician is tasked with providing secure remote access for employees who work from home. The solution must encrypt all traffic between the remote devices and the corporate network and must allow the remote devices to access internal resources (e.g., file servers, intranet) as if they were directly connected to the office LAN. Which of the following technologies should the technician implement?

Accepted Answer

VPN. A VPN (Virtual Private Network) is the correct technology because it creates an encrypted tunnel (using protocols like IPSec, OpenVPN, or WireGuard) between the remote device and the corporate network. This ensures all traffic is encrypted in transit and the remote device receives a virtual IP on the corporate LAN, allowing seamless access to internal resources such as file servers and intranets as if directly connected.

Answer

VLAN

Answer

DMZ

Answer

Port forwarding

Question 12

A support technician is troubleshooting a user's workstation that can successfully ping the loopback address (127.0.0.1) and the default gateway (192.168.1.1), but cannot access any internet websites. The user's web browser displays 'This site cannot be reached' for all URLs. Other devices on the same network can browse the internet without issue. The technician runs ipconfig and finds: IP 192.168.1.50, subnet mask 255.255.255.0, default gateway 192.168.1.1, DNS server 192.168.1.1. The technician can successfully ping 8.8.8.8 from the affected workstation. Which of the following is MOST likely the cause?

Accepted Answer

The DNS server setting is incorrect or the DNS server is not resolving names. The workstation can ping the loopback (127.0.0.1), the default gateway (192.168.1.1), and even a public IP (8.8.8.8), confirming that IP configuration, local network connectivity, and routing are all functional. However, it cannot resolve domain names to IP addresses, as evidenced by the browser's 'This site cannot be reached' error. Since the DNS server is set to 192.168.1.1 (the gateway), and the gateway is reachable, the issue is that the DNS server itself is not performing name resolution, or the workstation's DNS setting is incorrect (e.g., pointing to a non-functional DNS service on the gateway).

Answer

The default gateway is incorrectly configured

Answer

The network cable is faulty or the switch port is malfunctioning

Answer

The web browser is infected with malware that blocks all websites

Question 13

A user reports that their desktop computer is experiencing very slow network performance. The technician runs a speed test and gets only 10 Mbps download speed, while other devices on the same network achieve 500 Mbps. The technician checks the network adapter settings in the operating system and sees that 'Speed & Duplex' is manually set to '10 Mbps Half Duplex'. Which of the following should the technician do to resolve this issue?

Accepted Answer

Change the Speed & Duplex setting to 'Auto-Negotiation'. The issue is that the network adapter is manually locked to '10 Mbps Half Duplex', which forces a 10 Mbps connection even though the network infrastructure supports much higher speeds. Changing the setting to 'Auto-Negotiation' allows the adapter to automatically negotiate the highest mutually supported speed and duplex mode with the switch or router, restoring the expected 500 Mbps throughput.

Answer

Replace the Ethernet cable with a Cat5e cable

Answer

Update the network adapter driver

Answer

Disable and re-enable the network adapter

Question 14

A user reports that their workstation can access the internet and other network resources by IP address, but cannot connect to an internal file server (fileserver.company.local) by its hostname. Other users on the same network can access the file server by hostname without issue. The workstation's IP configuration is static: IP 192.168.1.10, subnet mask 255.255.255.0, default gateway 192.168.1.1, and DNS server 192.168.1.1. The technician pings the IP address of the file server (192.168.1.100) successfully from the affected workstation. Which of the following is the MOST likely cause of the issue?

Accepted Answer

The local hosts file has an incorrect mapping for the file server. The workstation can access resources by IP address but not by hostname, and other users can resolve the hostname successfully, indicating a local name resolution issue. The hosts file on the affected workstation likely contains an incorrect or outdated mapping for fileserver.company.local, overriding DNS resolution. Since the DNS server is working for other users and the workstation can ping the file server by IP, the problem is isolated to the local hosts file.

Answer

The workstation's network cable is faulty

Answer

The DNS server is not configured to resolve internal hostnames

Answer

A firewall rule is blocking port 445 (SMB) on the workstation

Question 15

A user is unable to print to a network printer. Other users on the same network can print to it successfully. The technician checks the user's workstation and confirms it has a valid IP address on the correct subnet. The printer's network cable is plugged in, and the link lights are active. Which of the following should the technician check FIRST?

Accepted Answer

The user's printer driver configuration. Since other users can print to the network printer successfully, the printer itself, its network connectivity, and the switch port are all functioning correctly. The issue is isolated to the user's workstation, and a valid IP address on the correct subnet indicates basic network connectivity is present. Therefore, the most likely cause is a misconfigured or corrupted printer driver on the user's machine, making the printer driver configuration the first thing to check.

Answer

The printer's toner or ink levels

Answer

The switch port that the printer is connected to

Answer

The network cable connecting the printer