Top 20 simplified CCNA certification questions with answers and examples

Read Time:5 Minute, 20 Second

Please keep in mind that the answers provided are based on general knowledge and may not cover all possible variations or specific scenarios. It’s always recommended to refer to the official Cisco documentation and study materials for accurate and up-to-date information.

What is the purpose of Spanning Tree Protocol (STP) in a network? STP prevents network loops. For example, if there are redundant links between switches, STP blocks some of these links to ensure there is only one active path between switches.
What is the default administrative distance for directly connected interfaces on Cisco routers? The default administrative distance for directly connected interfaces is 0. For instance, if a router has an interface connected to a network, it will have an administrative distance of 0 for that interface.
Which OSI layer handles logical addressing and routing? The Network layer (Layer 3) handles logical addressing and routing. For example, IP addresses are assigned at this layer, and routers operate at this layer to forward packets based on IP addresses.
What is the role of a default gateway in a TCP/IP network? The default gateway forwards network traffic between different networks. For instance, if a device in a local network wants to communicate with a device in a different network, it sends the traffic to the default gateway for forwarding.
Why are Access Control Lists (ACLs) used in networking? ACLs are used to filter network traffic based on specific criteria. For example, an ACL can be configured to allow or deny traffic based on source IP addresses, destination ports, or protocols.
How does TCP differ from UDP? TCP provides reliable, ordered data delivery with error detection and retransmission. For example, when you download a file from a server, TCP ensures that all data packets arrive intact and in the correct order. UDP, on the other hand, provides fast, unreliable data delivery without error detection or retransmission. It is often used for real-time streaming or voice communication where occasional packet loss is acceptable.
What does the Address Resolution Protocol (ARP) do? ARP maps IP addresses to MAC addresses in a local network. For example, when a device wants to send a packet to another device in the same network, it uses ARP to determine the MAC address of the destination device.
What is the purpose of Virtual Local Area Networks (VLANs)? VLANs logically divide a network into separate broadcast domains. For example, in a large organization, different departments can be assigned to separate VLANs to improve security and control network traffic.
How does static routing differ from dynamic routing? Static routing requires manual configuration of routing entries. For example, a network administrator can configure static routes on a router to specify the next hop for different networks. Dynamic routing protocols, on the other hand, automatically exchange routing information between routers. For instance, protocols like OSPF or EIGRP dynamically calculate the best paths for routing based on the network topology and update routing tables accordingly.
What is Network Address Translation (NAT) used for? NAT translates private IP addresses to public IP addresses and vice versa. For example, when multiple devices in a private network share a single public IP address to access the internet, NAT allows the translation of the private IP addresses to the public IP address.
What is the purpose of Dynamic Host Configuration Protocol (DHCP)? DHCP dynamically assigns IP addresses and network configurations to devices. For example, when a device connects to a network, it can request an IP address from a DHCP server, which will assign a unique IP address to that device.
What does Routing Information Protocol (RIP) do? RIP is a distance-vector routing protocol that determines the best path to a network based on hop count. For example, if there are multiple paths to reach a destination network, RIP will choose the path with the fewest hops.
What is the purpose of the Network Time Protocol (NTP)? NTP synchronizes device clocks to a common time reference. For example, in a network with multiple devices, NTP ensures that all devices have the same accurate time for synchronization and coordination.
What is the role of the Internet Control Message Protocol (ICMP)? ICMP provides error reporting and troubleshooting functionality in a network. For example, when a ping request is sent from one device to another, ICMP is used to send an echo request and receive an echo reply, indicating the connectivity status between the devices.
What is the function of a router? Routers forward data packets between different networks based on logical addresses. For example, if a packet needs to travel from one network to another, a router will examine the destination IP address and determine the best path for forwarding the packet.
What is the purpose of Dynamic Trunking Protocol (DTP)? DTP negotiates and automatically configures trunk links between switches. For example, when two switches are connected with a trunk link, DTP helps establish the trunk link by exchanging messages to determine if trunking is supported and configure the appropriate settings.
What is the purpose of Hot Standby Router Protocol (HSRP)? HSRP provides gateway redundancy by allowing multiple routers to share a virtual IP and MAC address. For example, if a primary router fails, another router with HSRP configured takes over the virtual IP and MAC addresses, ensuring uninterrupted network connectivity.
Why is Quality of Service (QoS) important in networking? QoS prioritizes and manages network traffic to ensure optimal performance for critical applications. For example, in a network where both voice and data traffic exist, QoS can be configured to give priority to voice traffic to ensure high-quality voice calls.
What does Virtual Router Redundancy Protocol (VRRP) provide? VRRP offers gateway redundancy by allowing multiple routers to act as a virtual router with a shared virtual IP address. For example, if the primary router fails, another router with VRRP configured takes over the virtual IP address, providing a redundant gateway for network devices.
What is the purpose of Secure Shell (SSH) protocol? SSH provides secure remote management of network devices through encryption and authentication. For example, network administrators can use SSH to securely access and manage routers, switches, and other devices remotely, preventing unauthorized access and data interception.

Please note that these examples are provided to illustrate the concepts. It’s important to study the CCNA topics in-depth and refer to official study materials for comprehensive preparation for the certification exam.

About Post Author

cobuman

Cobuman is an experienced IT professional who has dedicated his career to helping others succeed in the industry. With many years of experience in the field, he has become an expert in a variety of IT topics and is known for his ability to make complex concepts easy to understand. Cobuman's passion for sharing his knowledge with others has led him to create a series of free educational videos that cover a wide range of IT subjects. He is committed to providing working basic knowledge that helps beginners get IT jobs. Cobuman's videos are highly regarded in the industry for their ability to make IT education accessible to everyone. He understands the challenges that come with starting a career in IT, and his content is tailored to help individuals with little to no experience gain the skills and knowledge necessary to succeed. His dedication to helping others has made him a valuable resource in the IT community, and his videos continue to empower and inspire individuals looking to pursue a career in this exciting field.

https://cobuman.com