N10-009 Networking Concepts Practice Test 7 — 15 Questions

Question 1

At which OSI layer does a router primarily operate to make forwarding decisions based on IP addresses?

Accepted Answer

Layer 3 (Network). A router primarily operates at Layer 3 (Network) of the OSI model because it uses logical IP addresses (e.g., IPv4 or IPv6) to make forwarding decisions. The router examines the destination IP address in the packet header, performs a longest-prefix match against its routing table, and determines the next-hop interface. This layer is responsible for end-to-end delivery and path selection across multiple networks.

Answer

Layer 1 (Physical)

Answer

Layer 2 (Data Link)

Answer

Layer 4 (Transport)

Question 2

Which device operates at Layer 1 (Physical) of the OSI model and regenerates electrical signals to extend the distance of a network segment?

Accepted Answer

Hub. A hub operates at Layer 1 (Physical) of the OSI model. It receives incoming electrical signals on one port and regenerates (repeats) those signals out to all other ports, effectively extending the physical reach of a network segment. Unlike switches or routers, it performs no frame inspection or forwarding decisions.

Answer

Switch

Answer

Router

Answer

Bridge

Question 3

A workstation with IP address 10.0.1.5/24 needs to communicate with a server at 10.0.2.10/24. The workstation's default gateway is configured as 10.0.1.1. Which of the following will the workstation do with the IP packets destined for the server?

Accepted Answer

Send the packets to the default gateway.. The workstation's IP address (10.0.1.5/24) and the server's IP address (10.0.2.10/24) are on different subnets (10.0.1.0/24 vs. 10.0.2.0/24). When a host determines that the destination is not on the same local network, it will not attempt direct delivery via ARP. Instead, it forwards the IP packet to its configured default gateway (10.0.1.1), which then routes the packet toward the server's subnet.

Answer

Send the packets directly to the server using ARP.

Answer

Send the packets to the DNS server for resolution.

Answer

Drop the packets because the server is on a different network.

Question 4

A network administrator needs to connect 10 workstations in a way that each workstation's traffic does not collide with others. Which device should be used to connect these workstations?

Accepted Answer

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 destination port. This creates separate collision domains for each connected workstation, ensuring that traffic from one workstation does not collide with traffic from another.

Answer

Hub

Answer

Router

Answer

Modem

Question 5

Which of the following network topologies provides the highest level of redundancy and fault tolerance?

Accepted Answer

Mesh. A mesh topology provides the highest level of redundancy and fault tolerance because every node has a dedicated point-to-point connection to every other node. This means that if any single link or node fails, traffic can be immediately rerouted through multiple alternative paths without any single point of failure. In a full mesh, the number of links is n(n-1)/2, ensuring maximum path diversity and resilience.

Answer

Star

Answer

Bus

Answer

Ring

Question 6

Which of the following protocols is used to automatically assign IP addresses to devices on a network and also provides the subnet mask and default gateway?

Accepted Answer

DHCP. DHCP (Dynamic Host Configuration Protocol) is the correct answer because it is specifically designed to automatically assign IP addresses to devices on a network, along with essential configuration parameters such as the subnet mask and default gateway. When a DHCP client sends a discover message, the DHCP server responds with an offer that includes these details, allowing the client to fully participate in network communication without manual configuration.

Answer

DNS

Answer

ARP

Answer

ICMP

Question 7

A network switch that forwards frames based on MAC addresses operates at which layer of the OSI model?

Accepted Answer

Data Link. A network switch that forwards frames based on MAC addresses operates at Layer 2, the Data Link layer. This layer is responsible for node-to-node data transfer and error detection using MAC addresses, as defined by IEEE 802 standards. Switches build a MAC address table by learning source MAC addresses from incoming frames and use this table to make forwarding decisions.

Answer

Physical

Answer

Network

Answer

Transport

Question 8

A network has a single switch with VLANs 10, 20, and 30 configured. The switch is connected to a router that has three subinterfaces, each in a different VLAN. How many broadcast domains are present?

Accepted Answer

3. Each VLAN is a separate Layer 2 broadcast domain. With VLANs 10, 20, and 30 configured on the switch and a router using subinterfaces to route between them, there are exactly three broadcast domains — one per VLAN. Broadcasts are confined to their VLAN and do not cross VLAN boundaries without a Layer 3 device.

Answer

1

Answer

4

Answer

5

Question 9

Which of the following is a characteristic of UDP?

Accepted Answer

Has lower overhead than TCP. UDP (User Datagram Protocol) is a connectionless transport-layer protocol that provides minimal overhead compared to TCP. It does not establish a connection before sending data, nor does it provide reliability, flow control, or error recovery, making it ideal for real-time applications like VoIP and streaming where speed is prioritized over guaranteed delivery.

Answer

Provides guaranteed delivery

Answer

Uses sequence numbers

Answer

Supports three-way handshake

Question 10

A network administrator wants to logically segment a single physical switch into multiple separate broadcast domains without purchasing additional hardware. Which concept should be used?

Accepted Answer

Virtual LAN (VLAN). A VLAN logically segments a physical switch into multiple isolated broadcast domains by assigning switch ports to specific VLAN IDs (802.1Q). This prevents broadcast traffic from crossing VLAN boundaries without requiring additional hardware, as each VLAN functions as its own Layer 2 network.

Answer

Spanning Tree Protocol (STP)

Answer

Subnetting

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Quality of Service (QoS)

Question 11

At which layer of the OSI model does the conversion of data frames into electrical signals for transmission occur?

Accepted Answer

Layer 1 (Physical). Layer 1 (Physical) is responsible for the actual transmission of raw bits over a physical medium. This includes converting data frames received from Layer 2 into electrical signals (e.g., voltage levels on copper), light pulses (fiber optic), or radio waves (wireless). The Physical layer defines the hardware specifications, such as connectors, cable types, and signaling methods like Manchester encoding or NRZ.

Answer

Layer 2 (Data Link)

Answer

Layer 3 (Network)

Answer

Layer 4 (Transport)

Question 12

A junior network technician asks which device operates at Layer 2 of the OSI model and uses MAC addresses to forward frames. Which device is the technician describing?

Accepted Answer

Switch. A switch operates at Layer 2 (Data Link layer) of the OSI model and uses MAC addresses to make forwarding decisions. It builds a MAC address table by learning source MAC addresses from incoming frames and then forwards frames only to the specific port associated with the destination MAC address, reducing collision domains and improving network efficiency.

Answer

Hub

Answer

Router

Answer

Firewall

Question 13

Which network topology connects all devices to a central device?

Accepted Answer

Star. In a star topology, each device connects directly to a central device such as a switch or hub. This central device manages all communication between endpoints, meaning any data sent from one device must pass through the central point before reaching its destination. This design simplifies fault isolation because a single cable failure only affects the connected device, not the entire network.

Answer

Mesh

Answer

Bus

Answer

Ring

Question 14

A network technician is analyzing a small office network topology. An 8-port switch has 7 workstations directly connected. The remaining switch port is connected to a 4-port hub, which has 4 workstations attached. All devices are configured on the same VLAN and IP subnet. How many collision domains and broadcast domains are present in this network?

Accepted Answer

8 collision domains, 1 broadcast domain. Switches create a separate collision domain per port, so the 8-port switch provides 8 collision domains. The hub connected to one switch port extends that single collision domain to all its attached devices, but does not create new ones. All devices are on the same VLAN and IP subnet, so there is only one broadcast domain. Therefore, the network has 8 collision domains and 1 broadcast domain.

Answer

11 collision domains, 1 broadcast domain

Answer

12 collision domains, 5 broadcast domains

Answer

8 collision domains, 5 broadcast domains

Question 15

Match each network protocol to its well-known port number.

Accepted Answer

HTTP: 80. Common well-known ports: HTTP=80, HTTPS=443, FTP=21, SSH=22. The distractors swap these assignments.

Answer

HTTP: 443

Answer

FTP: 22