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CCNA Interview Questions

CCNA Interview Questions: Cracking a CCNA job interview at first attempt cab decide your fate on the spot. Providing relevant answers to CCNA interview questions create a wide scope for in the field as well as offer various opportunities. This article contains CCNA interview questionnaire, which has been developed by Aptron's CCNA specialists, CCNA experts, and CCNA trainers. They have put their sincere efforts and best of their knowledge while preparing CCNA interview questions and answers for freshers, and experience candidates. The questionnaire comprises of detailed answers covering basic and advanced CCNA interview questions. The questionnaire has been developed to help job candidates to crack interviews by providing relevant answers to their doubts or puzzlements. The CCNA Interview Questions is a summarization of verticals available in the CCNA technology.

ccna interview questions

About CCNA

CCNA (Cisco Certified Network Associate) is an IT certification in networking from Cisco Systems. CCNA certification is focuses on security, cloud, collaboration, security operations, design, data center technologies, industrial plants, service providers, and wireless. After completing the CCNA course training, candidates can explore jobs availability in any of the sector in the industry. The prominent domains such as manufacturing, wholesale, retail, services, and IT, requires CCNA networking professionals to handle their networking requirements and data routing.

CCNA Interview Questions And Answers

1. What are the two types of IP addresses available?

There are two types, namely IPv4 and IPv6

IPv4- 32 bit address and IPv6-128 bit address.

2. Which IP address is used for loopback address and for what purpose? is used for loopback address and also for local testing purposes.

Loopback means looping to our own systems, checking our own systems. It is used to test whether TCP/IP stack is correctly installed.

3. What do you mean by OSI layers?

Open System Interconnection (OSI)layers.

  • It is a set of rules used to describe how to make networks.
  • Whenever we design new network or hardware device, we have to follow OSI reference model.
  • There are seven layers, which means seven set of rules; they are designed by ISO (international standard organization).
  • It tells what are the services/ports/applications used.

4. What are the major functions of transport layer?

  • Segment fragmentation
  • Numbering segmenting
  • Reliable and unreliable data delivery
  • Error detection & error correction
  • Flow control
  • Multi tasking
  • Windowing

5. What is data encapsulation and data de-encapsulation?

  • When data is sent from a higher layer to a lower layer, each layer adds some information to the original data; this is called as encapsulation. The information added is called as header.
  • When data is sent from lower layer to higher layer, each layer will remove information from the other layer. This is called as de-encapsulation.

6. What are the major functions of routers?

  1. Packet switching- all incoming data is switched to packets. It deals only with packets (data with IP address)
  2. Packet filtering- router sends and receives only packets. It is used in WAN, so all incoming packets are filtered mainly for security.
  3. Internetwork communication- joining of two or more networks.
  4. Path selection- router is used to select the shortest and best path from source to destination.
  5. QoS- Quality of Service: QoS is the ability of the n/w to provide better or special service to a set of users or applications.

7. What is the main purpose of DHCP?

  • DHCP is dynamic host configuration protocol.
  • DHCP allows devices to acquire their addressing information dynamically.
  • DHCP is actually based on bootstrap protocol (bootp).
  • It is built on a client/server model and defines two components.
  1. Server- delivering host configuration information
  2. Client- requesting and acquiring host configuration information

8. What are the two types of cables available?

  • Straight through cable
  • Crossover cable

9. What Is The Purpose Of The Data Link?

The job of the Data Link layer is to check messages are sent to the right device. Another function of this layer is framing.

10. When Does Network Congestion Occur?

Network congestion occurs when too many users are trying to use the same bandwidth. This is especially true in big networks that do not resort to network segmentation.

11. What Is 100basefx?

100BASE-FX is a version of Fast Ethernet over optical fiber.

12. Utilizing Rip, What Is The Limit When It Comes To Number Of Hops?

The maximum limit is 15 hop counts. Anything higher than 15 indicates that the network is considered unreachable.

13. In Configuring A Router, What Command Must Be Used If You Want To Delete The Configuration Data That Is Stored In The Nvram?

Erase startup-config is the command to delete preconfigured files on the router.

14. What Is The Use Of “service Password Encryption”?

Service Password Encryption command encrypts plain text password into type 7 password. These are not very much secure and can be easily decrypted.

15. What Does Mtu Stand For?

MTU stands for “Maximum Transmission Unit.” When you configure a router, a default MTU is set. MTU determines the maximum size of a packet that is sent across the network. You can increase MTUs across the network, but this setting generally slows down the network compared to smaller MTU settings. Some network applications require larger MTU sizes, and that’s when you need to manually configure MTU sizes on your routers.

16. What are the advantages of using Switches?

Advantages of using Switches:

  • Switches are used to receive a signal and create a frame out of the bits from that signal. The signals enable you to get access and read the destination address and after reading that it forward that frame to appropriate frame. So, switches are the significant part of the transmission.

17. What is DLCI?

DLCI stands for Data Link Connection Identifiers. These are normally assigned by a frame relay service provider to identify each virtual circuit that exists on the network uniquely.

18. What is the difference between cross cable and straight cable?

Cross cables are used to connect the same group devices while straight cables are used to connect different group devices.

For example: If you want to connect one PC to another PC, you have to use cross cable while, to connect one switch to a router, you have to use a straight cable.

19. What is VLAN?

VLAN stands for Virtual Local Area Network.

20. What is the passive topology in CCNA?

When the topology enables the computers on the network only to listen and receive the signals, it is known as passive topology because they don't amplify the signals anyway.

21. What is RAID in CCNA?

RAID stands for Redundant Array of Independent Disks. RAID is a method which is used to standardize and categorize fault-tolerant disk systems. RAID levels provide various facilities like performance, cost, reliability, etc. These three are the mostly used RAID levels:

  • Level 0: (Striping)
  • Level 1: (Mirroring)
  • Level 5: (Striping and Parity)

22. What are the protocol data units (PDU) in CCNA?

Protocol data units (PDU) are the minimum possible units used at different layers of the OSI model to transport data.

Layers PDU
Transport Segments
Network Packets/Datagrams
Data-link Frames
Physical Bits

23. What is BootP?

BootP is a short form of Boot Program. It is a protocol that is used to boot diskless workstation connected to the network. BootP is also used by diskless workstations to determine its IP address and also the IP addresses of server PC.

24. What is a Frame Relay?

Frame Relay is used to provide connection-oriented communication by creating and maintaining virtual circuits. It is a WAN protocol that is operated at the Data Link and physical layer to sustain high-performance rating.

How frame relay works.

Frame relay multiplexes the traffic coming from different connections over a shared physical medium using special purpose hardware components such as routers, bridges, switch that packages the data into a frame relay messages. It reduces the network latency, i.e., the number of delays. It also supports the variable sized packet for the efficient utilization of network bandwidth.

25. What is Latency?

Latency is the amount of time delay. It is measured as the time difference between at the point of time when a network receives the data, and the time it is sent by another network.

26. What is the MAC address?

MAC address stands for Media Access Control address. This is an address of a device which is identified as the Media Access Control Layer in the network architecture. The MAC address is unique and usually stored in ROM.

27. What are the different types of the password used in securing a Cisco router?

There are five types of passwords can be set on a Cisco router:

  • Consol
  • Aux
  • VTY
  • Enable Password
  • Enable Secret

28. What Is Checksum?

A checksum is a count of the number of bits in a transmission data that is included with the data so that the receiver can check to see whether the same number of bits arrived. If the counts match, it’s assumed that the complete transmission was received.

29. What Are The Different Types Of Password Used In Securing A Cisco Router?

There are five types of passwords can be set on a Cisco router:

  1. Console
  2. Aux
  3. VTY
  4. Enable Password
  5. Enable Secret

30. What Is The Difference Between User Mode And Privileged Mode On A Cisco Router?

These two modes are somewhat self-explanatory. The user mode allows the user to view router status and basic system information. With privileged mode access status, the router can be configured and all status messages and errors can be viewed. User mode and privileged mode separates standard users on the network and network administrators who need to not only view router status but also make changes to the router’s configurations.

Career scopes and salary scale

The average job crisis is rising across job markets. But, when it is concerning to networking professionals, the requirement of CCNA professionals are at higher side. CCNA aspirants having in-depth knowledge and skill-based training are able find quick jobs at better salaries across the industry. CCNA networking professionals are required in every place. A CCNA candidate is expected a minimum salary of 30, 000 dollars per annum. But, this figure is not the last digit. Once the candidate is able to attain experience and skill in the field, the salary assurance gets to double. The salaries are very reliant upon the location, business, and the company’s requirements.


The article ‘CCNA interview questions’ has been productively answered every advanced CCNA interview questions. As well, the considerate planned of the CCNA interview questions for experienced is being designed by our trainers and team of experts. They have tried their top of knowledge to aid professionals in getting answers to all doubts and not clear concepts. Even then, if learners still necessitate more detailing about CCNA, then they may drop in a message to our experts regarding CCNA interview questions for experienced professionals. Our trainers would be happy to assist and resolve all your CCNA-programming issues of the students. Join CCNA Training in Noida, CCNA Training in Delhi, CCNA Training in Gurgaon

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