220-1101 Networking Practice Test 13 — 15 Questions

Question 1

A technician installs a new PoE security camera in an office. The camera is connected to a wall jack that runs to a PoE-enabled switch. The camera does not power on. The technician tests the cable with a cable tester and it passes. The switch port has a solid link light. The technician connects a known-working laptop to the same wall jack, and the laptop gets an IP address and can access the network. Which of the following is the MOST likely cause of this issue?

Accepted Answer

The camera requires a higher PoE standard than the switch provides.. The camera does not power on despite the cable passing a continuity test, the switch port showing a link light, and a known-working laptop successfully obtaining an IP address through the same wall jack. This indicates that the physical layer and basic network connectivity are functional, but the PoE power delivery is insufficient. The most likely cause is that the camera requires a higher PoE standard (e.g., PoE+ 802.3at, which provides up to 30W) than the switch provides (e.g., standard PoE 802.3af, which provides up to 15.4W), so the camera cannot draw enough power to boot.

Answer

The cable is too long for PoE to function correctly.

Answer

The switch port does not have PoE enabled.

Answer

The camera has an IP address conflict with another device on the network.

Question 2

A technician is setting up a small office network with 15 computers, a router, and an unmanaged switch. The computers are configured with static IP addresses. After connecting all computers to the switch, the technician notices that some computers can communicate with each other but cannot access the internet. The router's LAN IP is 192.168.1.1 with subnet mask 255.255.255.0. The computers have IP addresses in the range 192.168.1.2-192.168.1.16 with default gateway 192.168.1.1. The technician pings the router from a computer that cannot access the internet, and the ping times out. Which of the following is the MOST likely cause?

Accepted Answer

The Ethernet cable connecting the switch to the router is faulty.. The ping from a computer to the router (192.168.1.1) times out, indicating that Layer 3 connectivity to the router is absent. Since the switch is unmanaged and operates at Layer 2, it does not perform VLAN routing or filtering; the most likely cause is a physical or data-link layer issue on the link between the switch and the router, such as a faulty Ethernet cable. A faulty cable would prevent frames from reaching the router, causing the ping timeout and the inability to access the internet.

Answer

The switch is not forwarding traffic to the router due to a VLAN mismatch.

Answer

The computers are configured with the wrong subnet mask.

Answer

The router's firewall is blocking ICMP traffic.

Question 3

A network administrator is setting up a new wireless network for a small business. The administrator configures a wireless access point with WPA2-PSK and a strong passphrase. Several users on different floors report intermittent connectivity and slow speeds. The administrator checks the access point and finds that the signal strength is excellent in the area. The access point is dual-band (2.4GHz and 5GHz) and broadcasts a single SSID. Which of the following is the MOST likely cause of the issue?

Accepted Answer

The channel width is set to 40MHz on the 2.4GHz band, causing interference.. In the 2.4 GHz band, using a 40 MHz channel width consumes more spectrum and overlaps with adjacent channels, causing co-channel and adjacent-channel interference. This interference leads to intermittent connectivity and slow speeds, especially on different floors where signal propagation is more complex. The strong signal strength and dual-band setup with a single SSID point to channel width misconfiguration as the most likely cause.

Answer

The access point is configured to use the default IP address, causing an IP conflict.

Answer

The encryption type is too weak for the number of users.

Answer

The access point's firmware is outdated and needs an update.

Question 4

A technician is configuring a small office network with a PoE-managed switch and several VoIP phones. All phones are connected and working except one. On the non-working phone, the Ethernet link light is solid on both the phone and the switch port, but the phone's display remains dark and it does not power on. The technician has verified the cable with a tester and it passes. The switch port is enabled and configured for the same VLAN as other working phones. Which of the following is the MOST likely cause?

Accepted Answer

The switch port's PoE power budget has been exceeded.. A PoE-managed switch allocates power from a finite budget. If the total power draw of all connected devices exceeds the switch's PoE power budget, the switch may deny power to additional devices even if the port is administratively enabled and the link is up. The solid Ethernet link light indicates Layer 1 connectivity, but the phone's dark display and lack of power suggest it is not receiving PoE, which is consistent with the switch having exhausted its PoE budget.

Answer

The phone's MAC address is incorrect.

Answer

The cable is a crossover cable.

Answer

The switch port is in a different subnet.

Question 5

A network technician configures a managed switch with two VLANs: VLAN 10 for workstations and VLAN 20 for servers. A workstation on VLAN 10 can ping its default gateway (192.168.10.1), and a server on VLAN 20 can ping its default gateway (192.168.20.1). However, the workstation cannot ping the server's IP address (192.168.20.10). All switch ports are configured as access ports in their respective VLANs, and the default gateways are correctly assigned. Which of the following is MOST likely needed to allow this communication?

Accepted Answer

A router configured for inter-VLAN routing. The workstation and server are on different VLANs, which are separate Layer 2 broadcast domains. Even though each device can reach its own default gateway, communication between VLANs requires a Layer 3 device to route packets between them. A router configured for inter-VLAN routing (either router-on-a-stick or a Layer 3 switch) is necessary to forward traffic from VLAN 10 to VLAN 20.

Answer

A DHCP server on each VLAN

Answer

A higher category Ethernet cable

Answer

A trunk port between the switch and the router

Question 6

A small office uses a single router with DHCP enabled for 50 devices. Recently, some devices cannot obtain an IP address, while others work fine. The technician checks the DHCP lease table and sees that it is nearly full with 49 active leases. The network uses a default Class C subnet (255.255.255.0). Which of the following is the MOST appropriate solution to ensure all devices can obtain an IP address in the future?

Accepted Answer

Increase the DHCP scope size by changing the subnet mask to /23 (255.255.254.0).. Option C is correct because the default Class C subnet mask /24 (255.255.255.0) provides only 254 usable IP addresses, but the DHCP scope is limited to a smaller range (often 192.168.1.1–192.168.1.254). With 49 active leases out of a typical default pool of 50–100 addresses, the scope is nearly exhausted. Changing the subnet mask to /23 (255.255.254.0) expands the network to 510 usable addresses, doubling the DHCP scope and ensuring all 50 devices can obtain IP addresses without exhausting the pool.

Answer

Change the router's LAN IP address to a different private subnet, such as 10.0.0.1/8.

Answer

Reduce the DHCP lease time so that addresses are recycled more frequently.

Answer

Disable DHCP on the router and assign static IP addresses to all devices.

Question 7

A technician is troubleshooting a workstation that can access internal network resources and the internet, but users report that they cannot browse websites using domain names (e.g., www.example.com). The technician opens a command prompt and successfully pings a public IP address (8.8.8.8), but pinging www.google.com returns 'Ping request could not find host'. The workstation receives IP settings via DHCP. Which of the following is the MOST likely cause?

Accepted Answer

The DNS server addresses are not being provided by DHCP. The workstation can ping a public IP address (8.8.8.8) but cannot resolve domain names like www.google.com. This indicates that IP connectivity is working, but DNS resolution is failing. Since the workstation receives IP settings via DHCP, the most likely cause is that the DHCP server is not providing correct DNS server addresses, leaving the workstation without a valid DNS resolver.

Answer

The default gateway is misconfigured

Answer

The workstation's firewall is blocking DNS traffic

Answer

The router's NAT is misconfigured

Question 8

A user reports that their workstation cannot access the internet. The technician runs ipconfig and sees that the workstation has an IP address of 169.254.23.45 with a subnet mask of 255.255.0.0. The technician checks the network cable and link lights; they are normal. Which of the following is the MOST likely cause?

Accepted Answer

The DHCP server is not responding. The IP address 169.254.23.45 with a subnet mask of 255.255.0.0 is an Automatic Private IP Addressing (APIPA) address, which Windows assigns when a DHCP server cannot be reached. Since the link lights are normal and the cable is not faulty, the most likely cause is that the DHCP server is not responding, preventing the workstation from obtaining a valid IP address.

Answer

The Ethernet cable is faulty

Answer

The DNS server is misconfigured

Answer

The default gateway is incorrect

Question 9

A user reports that their workstation cannot access the internet or any network resources. The technician runs ipconfig and sees the IP address 169.254.10.55 with subnet mask 255.255.0.0. The Ethernet link lights are solid on both the NIC and the switch port. Which of the following is the MOST likely cause?

Accepted Answer

B. The IP address 169.254.10.55 with subnet mask 255.255.0.0 is an Automatic Private IP Addressing (APIPA) address, assigned by Windows when a DHCP server is unavailable. Since the link lights are solid, the physical layer is functional, but the workstation cannot obtain a valid IP address, indicating the most likely cause is a DHCP server failure or misconfiguration.

Answer

A

Answer

C

Answer

D

Question 10

A technician is setting up a small office network with a managed switch, a router (192.168.1.1/24), and 20 workstations. All workstations are connected to the switch and configured with static IPs in the range 192.168.1.2-192.168.1.21, subnet mask 255.255.255.0, default gateway 192.168.1.1. All workstations can ping the router successfully, but some workstations cannot ping each other. Which of the following is the MOST likely cause?

Accepted Answer

A. The most likely cause is that the managed switch has VLANs configured, separating workstations into different broadcast domains. Even though all workstations are on the same IP subnet (192.168.1.0/24), if they are assigned to different VLANs, the switch will not forward frames between them unless a router or Layer 3 switch is configured for inter-VLAN routing. Since the workstations can reach the router (which may be on a trunk or access port in a specific VLAN), but not each other, this points to VLAN segmentation as the root cause.

Answer

B

Answer

C

Answer

D

Question 11

A user reports that their workstation can access local network shares and printers but cannot access the internet. The technician pings the default gateway (192.168.1.1) successfully. The technician pings a public DNS server (8.8.8.8) and the request times out. Which of the following is the MOST likely cause?

Accepted Answer

The router's WAN connection is not functioning. The technician can ping the default gateway (192.168.1.1) successfully, confirming that the workstation's local IP configuration and Layer 2/3 connectivity to the router are correct. However, pinging the public DNS server 8.8.8.8 times out, which indicates that traffic is reaching the router but cannot exit to the internet. This points to a failure in the router's WAN connection (e.g., the modem or ISP link), as the router itself is reachable but cannot forward packets beyond the local subnet.

Answer

Incorrect DNS server configured on the workstation

Answer

The workstation's default gateway is misconfigured

Answer

The workstation's subnet mask is incorrect

Question 12

A technician connects a new workstation to a managed switch port that is configured with PortFast and BPDU guard. The workstation obtains an IP address via DHCP and can ping its own IP address, but it cannot ping any other devices on the local network, including the default gateway. The link light on both the NIC and switch port is solid green. On the switch, the port status shows 'errdisable' with the reason 'BPDU guard'. Which of the following is the MOST likely cause of this issue?

Accepted Answer

The workstation's NIC is running Spanning Tree Protocol, which the switch's BPDU guard detected and shut down the port.. BPDU guard is a security feature that disables a PortFast-enabled port if it receives any Bridge Protocol Data Unit (BPDU). A workstation NIC should never send BPDUs, but some NICs or their drivers (e.g., when teaming or virtualization software is active) may inadvertently run Spanning Tree Protocol (STP) and generate BPDUs. When the switch receives a BPDU on a BPDU guard-protected port, it immediately places the port into errdisable state, blocking all traffic except the link light remains solid. This explains why the workstation can obtain an IP (DHCP traffic occurred before the port was disabled) but cannot ping any other devices after the port is errdisabled.

Answer

The workstation's firewall is blocking traffic.

Answer

The switch port is configured as an access port in the wrong VLAN.

Answer

The workstation's NIC has a static IP address that conflicts with another device.

Question 13

A user reports that they cannot access the company intranet website at http://intranet. The technician opens a browser on the workstation and types the IP address 192.168.10.5, which successfully loads the intranet page. The workstation is configured to obtain IP settings automatically via DHCP. Which of the following is the MOST likely cause of the issue?

Accepted Answer

The DHCP server is not providing a DNS server address. The user can access the intranet by IP address but not by hostname, which indicates a name resolution failure. Since the workstation uses DHCP, the most likely cause is that the DHCP server is not providing a DNS server address, so the browser cannot resolve 'intranet' to an IP. This is a classic symptom of missing or misconfigured DNS settings from DHCP.

Answer

The intranet server is down

Answer

The workstation has a corrupted hosts file

Answer

The workstation's browser cache is full

Question 14

A technician is configuring a small office network with a managed switch. A new employee's workstation is connected to port 12 on the switch. The workstation receives an IP address from the DHCP server and can ping the default gateway (192.168.1.1), but it cannot ping the file server at 192.168.1.50. Other workstations on the same subnet can ping the file server. The technician checks the switch configuration and sees that port 12 is assigned to VLAN 10, while all other workstations and the file server are on VLAN 1. Which of the following is the MOST likely reason the workstation cannot reach the file server?

Accepted Answer

The switch port is configured as an access port in the wrong VLAN. The workstation is on VLAN 10 while the file server and other workstations are on VLAN 1. By default, VLANs segment broadcast domains and isolate Layer 2 traffic; a device on VLAN 10 cannot communicate with a device on VLAN 1 unless a Layer 3 device (router or Layer 3 switch) routes between them. Since the switch port is configured as an access port in VLAN 10, it is the wrong VLAN assignment that prevents the workstation from reaching the file server.

Answer

The workstation's subnet mask is incorrect

Answer

The workstation's firewall is blocking traffic

Answer

The DHCP server assigned an IP from a different scope

Question 15

A technician is setting up a new workstation. After connecting the Ethernet cable, the link light on the NIC and the switch port are solid green. The technician runs ipconfig and sees an IP address of 169.254.3.45 with a subnet mask of 255.255.0.0. The workstation cannot ping the default gateway or any other network devices. Which of the following is the MOST likely cause?

Accepted Answer

The DHCP server is unavailable or unreachable. The 169.254.x.x address with a /16 subnet mask is an Automatic Private IP Addressing (APIPA) address, assigned by Windows when a DHCP server is unreachable. The solid link lights confirm Layer 1 connectivity is good, so the issue is that the workstation cannot obtain a valid IP from a DHCP server, preventing communication with the default gateway.

Answer

The Ethernet cable is faulty

Answer

The workstation's subnet mask is incorrect

Answer

The NIC driver is corrupted