Navigating through the vast domain of networking, Cisco’s CCNA certification remains a gold standard for network professionals. The certification is designed to validate one’s knowledge of network fundamentals, network access, IP connectivity, IP services, security fundamentals, and automation and programmability.
To help you prepare for this esteemed certification, we’ve compiled a practice test of 25 multiple-choice questions, each paired with answers and explanations to enhance your learning experience. Let’s dive in!
1. Which of the following protocols operate at the Transport layer of the OSI model?
Answer:
Explanation:
The Transport layer of the OSI model is responsible for end-to-end communication and error recovery. TCP (Transmission Control Protocol) operates at this layer, ensuring reliable and ordered delivery of data packets.
2. What is the purpose of a subnet mask in IP addressing?
Answer:
Explanation:
A subnet mask is used to divide an IP address into network and host portions. It helps in identifying the network portion of an IP address, enabling proper routing of packets.
3. Which Cisco command will display the routing table on a router?
Answer:
Explanation:
The "show ip route" command is used on Cisco routers to display the IP routing table, which contains information on connected and learned routes.
4. What is the default administrative distance of OSPF?
Answer:
Explanation:
Administrative distance is a metric used to rate the trustworthiness of routing information. The default administrative distance for OSPF (Open Shortest Path First) is 110.
5. Which of the following is a characteristic of a switch as compared to a hub?
Answer:
Explanation:
Unlike hubs, switches are intelligent devices that learn and store MAC addresses to forward data frames only to the specific port where the destination device is connected, reducing network traffic.
6. What is the function of the Spanning Tree Protocol (STP)?
Answer:
Explanation:
The Spanning Tree Protocol (STP) is designed to prevent switching loops in a network. It blocks redundant paths, leaving only one active path between network devices.
7. Which type of cable is used to connect two similar devices, such as connecting two routers?
Answer:
Explanation:
A crossover cable is used for connecting two similar devices, such as two routers or two switches. It has opposite pinouts on either end, allowing for direct device-to-device connections.
8. How many bits are in an IPv6 address?
Answer:
Explanation:
IPv6 addresses are 128 bits long, providing a vastly larger address space compared to the 32-bit IPv4 addresses.
9. What is the purpose of VLANs in a switched network?
Answer:
Explanation:
VLANs (Virtual Local Area Networks) are used in switched networks to create separate broadcast domains, which helps in reducing broadcast traffic and increasing network efficiency and security.
10. What command is used to save the running configuration to the startup configuration on a Cisco device?
Answer:
Explanation:
On Cisco devices, the commands “copy run start” and “write memory” are used to save the running configuration to the startup configuration.
11. Which protocol is used to automatically assign IP addresses to devices on a network?
Answer:
Explanation:
The Dynamic Host Configuration Protocol (DHCP) is used to automatically assign IP addresses and other network configuration information to devices on a network.
12. What is the purpose of NAT (Network Address Translation) in a network?
Answer:
Explanation:
NAT (Network Address Translation) is used to translate private IP addresses to public IP addresses. This allows multiple devices on a local network to be mapped to a single public IP address, enabling them to access the internet.
13. Which of the following is a classless routing protocol?
Answer:
Explanation:
OSPF (Open Shortest Path First) is a classless routing protocol, meaning it supports VLSM (Variable Length Subnet Mask) and CIDR (Classless Inter-Domain Routing), allowing for better IP address utilization and route summarization.
14. What port number is used by SSH (Secure Shell)?
Answer:
Explanation:
SSH (Secure Shell) uses port number 22. It is a protocol used to securely log into remote systems and for secure file transfers with encryption.
15. Which of the following commands will configure a router interface with the IP address 192.168.1.1 and subnet mask 255.255.255.0?
Answer:
Explanation:
In the Cisco IOS command-line interface, the correct command to assign an IP address to an interface is ip address [ip] [subnet mask].
16. How does a switch handle a unicast frame with a destination MAC address not in its MAC address table?
Answer:
Explanation:
If a switch receives a unicast frame and the destination MAC address is not in its MAC address table, it will flood the frame out of all ports except the port on which the frame was received.
17. Which of the following protocols is used for VPNs to secure communication over an untrusted network?
Answer:
Explanation:
IPsec (Internet Protocol Security) is a suite of protocols used to secure Internet Protocol (IP) communications by authenticating and encrypting each IP packet in a communication session.
18. What is the function of the Wireless Access Point (WAP) in a wireless network?
Answer:
Explanation:
A Wireless Access Point (WAP) serves as an interface between wireless devices and the wired LAN, allowing the wireless devices to communicate with the wired network and other devices on the network.
19. Which security measure can be used to mitigate the risk of a brute force attack on network passwords?
Answer:
Explanation:
Using strong, complex passwords is essential in mitigating the risk of brute force attacks, where an attacker tries to gain access by systematically checking all possible passwords until the correct one is found.
20. In a Cisco device, which configuration mode should you be in to set the device hostname?
Answer:
Explanation:
To set the hostname on a Cisco device, you should be in the Global configuration mode. The command to set the hostname is hostname [name].
21. Which of the following automation tools can be used for network automation and programmability?
Answer:
Explanation:
Python is a popular scripting language used for network automation and programmability due to its readability, ease of learning, and extensive libraries.
Successfully passing the CCNA exam is a significant milestone in the journey of a network professional. This set of practice questions is designed to simulate the experience and challenge of the real exam, helping you understand the intricacies of networking concepts. Keep practicing, explore additional resources, and remember: that every step forward is a step closer to achieving your CCNA certification. Good luck, and may your journey in networking be prosperous and enlightening!