CCNA Interview Questions & Answers

Frequently Asked CCNA Interview Questions and Answers

The CCNA course is a leading computer network certification issued by Cisco Systems. This helps candidates become familiar with technology areas such as networking, security, and automation. Cisco Certified Network Associate CCNA Interview Questions and Answers.

 The CCNA certification provides candidates with the opportunity to learn the basics of CCNA and prepare for recent network advances. As 99% of companies use qualifications to make hiring decisions, employees must have the right qualifications.

 Large companies around the world rely on IT services to function effectively and economically. On the technical side of the CCNA technician, make sure that network devices such as routers, switches, and firewalls are functioning properly. Therefore, the CCNA Interview Questions and Answers certification pass helps individuals gain expertise in networking systems in the IT sector.

14 CCNA Interview Questions and Answers that will help you to get Desired Job

CCNA Interview Questions and Answers for Fresher Candidates

1. What is Routing?

Routing is the process of deciding the route for a data packet to reach its destination. This is the process of choosing a path that spans one or more networks to move a packet of data from source to destination. Routing is commonly performed on many types of networks, including circuit-switched networks and computer networks. It is considered one of the most important features of the network and is performed by a device called a router.  In the figure above, the data packet is moving from computer A to computer B. You can use two paths.

  1. Networks 1, 3, and 5

 2. Networks 2 and 4

 It depends on whether the network router goes through the first or second path. The first is a long path, but packets can be routed faster, and the second is a shorter path. These are the kind of decisions that routers must always make

2. Tell me about IT Networking?

Networking is the act of creating touch and changing records with different humans, groups, and establishments to expand at the same time useful relationships or to get the right of entry to and proportion records among computers.

An instance of networking is handing out your enterprise card at a social occasion that is designed to offer possibilities for brand new enterprise collaborations to shape and to carry collectively potential employers and proficient new humans that can be searching out a brand new employment position.

Networks are used to connect to and work with networks. This is the process of creating and using wired or wireless networks to exchange information, ideas, files, and other electronic communications.

3. What do you know about Protocols?

This is the digital language used to communicate with others on the Internet. The importance of a protocol is that it is a set of mutually accepted rules that are implemented at both ends of a communication channel in order to properly exchange information. By applying these rules, two devices can communicate with each other and exchange information.

Don’t even imagine using the Internet without a protocol. Each protocol has a unique name and is defined with different terms and uses. Sending a message from a sender to a receiver over a medium (the media is the physical path through which the message travels) using a protocol.

4. What do you know about data packets in Networking?

Everything that flows through the network can be classified as part of the data contained in the packet. A network packet or IP packet can be described as a unit of data (approximately 1KB to 1.5KB) flowing from a source on the Internet or packet-switched network to a destination address (sender to receiver).

These are the basic units of information transmission over a network because each piece of information sent by a sender is divided into smaller structures and sent easily and quickly over a network connection. Without these fragments, it would be much more difficult to move large amounts of information over the network.

The OSI model conceptual framework provides a set of protocols in which data is divided into smaller layers before transmission and reassembled when the destination address is reached. In general, the networks we use today run on a TCP / IP protocol stack that is transmitted over a physical network derived from Ethernet.

5. Why a Router is important for Networking?

The router is currently functioning as a modem, and the modem converts digital-analog signals and analog to analog signals. Analog signal  Next, the router converts an analog signal into a computer system digital signal.

 Another function of a router is that the router filters network traffic with a specific protocol, not a packet address. The router also logically shares the network instead of physical instead. The IP router can divide the network into different subnets, and only data traffic for a particular IP address may be configured between segments. This type of intelligent routing often slows down your network. Such filtering takes longer than using a switch or bridge that looks only at Ethernet addresses. However, in more complex networks, using routers can improve overall efficiency.

6. How many types of routers are there?

Mainly There are 3 types of routers:

Static route:

Also known as a non-adaptive route, at static route the user can configure it directly on the router’s active interface or manually add it to the routing table by your administrator.

Default Route:

This is where the router is configured to send all packets to a single router, regardless of whether it belongs to a particular network. This is especially used when the network operates at a single exit point.

Dynamic route:

This route is also known as an adaptive route. It automatically adjusts routes according to the current status of routes in the routing table and uses routing protocols to find destinations in the network.

CCNA Interview Questions and Answers for Experienced Candidates

7. Explain Network Switches in details?

Networks are essential today to support businesses, provide communication, and provide entertainment-the list goes on and on. A basic element common to networks is a network switch. This helps connect devices to share resources.

A network switch is a device that operates at the data link layer (Layer 2) of the OSI model. It receives and resends packets sent from devices connected to the physical port, but only through the port that leads to the device to which the packet is expected to arrive. You can also work at network layer 3 where routing takes place.

When a device is connected to a switch, the switch remembers its media access control (MAC) address. This is the code written to the network interface card (NIC) of the device connected to the Ethernet cable connected to the switch. The switch uses the MAC address to identify the connected device that identifies the source of outgoing packets and the destination of incoming packets. CCNA Interview Questions and Answers.

 Therefore, the MAC address identifies the physical device as opposed to the network layer (Layer 3) IP address, which is dynamically assigned to the device and can change over time. 

 When a device sends a packet to another device, that device enters the switch, which reads the header to determine how to handle it. Matches one or more destination addresses and sends the packet over the appropriate port to the destination device. To reduce the possibility of simultaneous network traffic collisions between the switch and the connected device, most switches provide full dual functionality, and packets sent to and received from the device are the full bandwidth of the switch connection.

Also Check , Implementing And Administering Cisco Solutions (CCNA) Training

8. How a Router is different from a Switch?

The switch facilitates resource sharing by connecting all devices on a small business network, including computers, printers, and servers. Thanks to the switch, these connected devices can exchange information and communicate with each other, regardless of where they are in the building or campus. Without a switch to connect devices, it would be impossible to build a small business network.

Just as a switch connects multiple devices to create a network, a router connects multiple switches to each network to form a larger network. These networks can be located in a single location or multiple locations. If you want to build a small business network, you need one or more routers. Routers not only connect multiple networks but also allow network devices and multiple users access to the Internet.

 Ultimately, the router acts as a dispatcher, forwarding traffic and choosing the most efficient route to get information in the form of data packets sent over the network. Routers connect businesses to the world, protect information from security threats, and determine which device takes precedence over other devices.

9. Why does Network Congestion happen?

Network congestion refers to poor quality of service (QoS), resulting in packet loss, queue delay, or blocked new connections. Network congestion typically occurs when traffic is congested and a network link or node is processing more data than it can handle.To avoid confusion and reduce the impact of network congestion, organizations use different congestion prevention and control methods.

 If there is too much traffic in the form of vehicles, the highway will be congested. Similarly, when a network is overloaded with data, it becomes congested. Also, as on the road, network congestion can be a sign of temporary conditions such as increased traffic or attacks, or more serious and chronic problems such as pending repairs or misconfigurations. These problems require a more comprehensive solution.

From the end user`s factor of view, community congestion may be perceived as gradual reaction instances or “slowing down the community”. If the internet, Wi-Fi, or maybe the pc itself feels “gradual,” it is frequently the end result of community congestion. But this is now no longer the handiest congestion in community traffic.

10. How can you fix the Network Congestion?

To solve congestion within a network, we can do the following:

  • Monitor and analyze network traffic

The starting point for solving most network congestion problems is to monitor and analyze network traffic, especially if there are too many devices, the devices are overloaded, or the network design is poor. This helps to identify potential bottlenecks and highlight underutilized areas that are ready to be reallocated to improve performance. Gain insight into network traffic and take intelligent action to reduce network congestion.

  • Bandwidth

Networks that can carry more data are less likely to experience congestion issues. A simple solution to increase the amount of information that can be sent is to increase the bandwidth of your network. It is important to remember the general saying. This applies to networks in many ways. The slowest component of a network is usually related to its overall performance. After monitoring your network to see how traffic is flowing, you can upgrade the slowest parts of your network to maximize the benefits of increasing bandwidth.

  • Segmentation and prioritization

 Traffic monitoring has additional benefits. It is the ability to design or redesign a bespoke optimized network for each business. Do this by dividing the network into smaller subnets, leaving room for practical prioritization and increasing efficiency. This creates a healthier network and allows more accurate monitoring by increasing or decreasing traffic as needed to affect the areas that are mostly affected by network congestion.

11. Why do we need the Data Link and Transport Layer?

  • Data Link Layer

This is the second layer of the OSI model and is typically responsible for sending datagrams over a single link. It is considered one of the most complex layers and has complex features and drawbacks. Also, make sure that the appropriate physical protocol is assigned to the data.

  • Transport Layer

This is the fourth layer of the OSI model, which provides transparent data transmission between end-users and reliable data transmission services to the top layer. Its main goal is to deliver the entire message from source to destination.

12. Explain the difference between Tracert & Traceroute?

Tracert is a command prompt command used to display various details about the path a packet takes from the source computer to the specified destination computer. It uses ICMP or the Internet Control Message Protocol to repeat only  the order-requests. It can be used on a PC. This command is commonly used on Windows NT-based operating systems.

On the other hand, Traceroute, as the name implies, is the command used to trace a record of the path that a packet follows from the source computer to the specified destination computer. Uses UDP (User Datagram Protocol) echo requests. The Traceroute command can be used on a router or switch. This command is commonly used on UNIX operating systems.

13. Explain Frame Relay in short?

Frame Relay is a packet-switched technology that is fragmented into transmission units called frames and transmitted in high-speed bursts over a digital network. Establishes an exclusive connection called a virtual connection during the transmission period.

 It uses a technology called fast packets, and error checking is done last, not at the middle node of the transmission. This makes it more efficient and faster than X.25 (transfers above 2,044 Mbit / s are possible).

 Another advantage is that it requires less powerful exchanges (nodes) with less storage capacity than the X25. If you have a lot of traffic and a lot of small packets, its performance is better than the X25. 

 If large files are transferred at high speed, the X25 is cost-effective.

14. What is VLAN?

Essentially, a VLAN is a collection of devices or network nodes that communicate with each other as if they were forming a single LAN, even if they reside in one or more LAN segments. Technically, a segment is separated from the rest of the LAN by a bridge, router, or switch and is typically used in a particular department. This means that packets sent by the workstation will reach all other workstations on the VLAN, but not the outside world.

 This simplifies many of the complex issues that LANs can cause, such as excessive network traffic and collisions. If two workstations send data packets at the same time on a hub-connected LAN, the data will collide and will not be sent correctly. Collisions propagate throughout the network. That is, the LAN is busy and the user must wait for the collision to propagate completely across the network before it can be operational again. At that point, you need to resend the original data.

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These are only the most-asked questions in the CCNA interview questions and answers , but the syllabus itself is vast, and Vinsys is offering you the best CCNA training at affordable pricing. Our CCNA training classes can be customized and we have the best tutors with an ocean of knowledge about CCNA and the relevant fields.


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