“Get certified internationally and work anywhere in the world” has been the recruitment trends of the few of the world’s best technology companies. Tech giants like Microsoft, Cisco, Oracle are some of the leading companies which provide international certifications online including the most preferred certifications in networking are CCNA from Cisco Systems, USA.
With more than 50 percent of the world’s networking market, Cisco certification opens up multiple employment avenues for aspirants. We are listing 16 most asked CISCO interview questions at all IIHT placement drives and across the industry.
Certification: Cisco Certified Network Associate
Exam code: 200-125
Q #1) Define a Protocol
Protocol is defined as the rules that connect two or more devices to transfer the information from one device to another. It helps to know how data is being transferred from one network to another network for communication.
Q #2) What is OSI reference model?
OSI is a reference model that tells how information and data are communicated over a network. It is a conceptual framework that understands the relationships of transmission.
Q #3) What are the different layers of OSI model?
Basically, there are 7 layers of OSI model with its own functionality in the OSI model.
- Layer 1 – Physical
- Layer 2 – Data Link Layer
- Layer 3 – Network
- Layer 4 – Transport
- Layer 5 – Session
- aLayer 6 – Presentation
- Layer 7- Application
Q #4) What is a Switch and why we are using Switches?
Switch is used to receive the signal to create a frame. It forwards the packets between various LAN segments. It supports packet control when the data is sent to Data Link layer or Network layer of the OSI model.
While sending packets, a signal gets enabled and gets accessed by reading the destination address and forwards the frame to appropriate frame, hence we use switches.
Q#5) What are the major functions of transport layer?
- Segment fragmentation
- Numbering segmenting
- Reliable and unreliable data delivery
- Error detection & error correction
- Flow control
Q#6) 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:
- Server- delivering host configuration information
- Client- requesting and acquiring host configuration information
Q#7) What are the two types of routes available in routers?
- Static or Static default
Static, if one route is fixed for transmission it will stay fixed. If that link is down it cannot connect and reach the destination even if there are alternate paths. Static route is used for smaller networks. Symbol of static is s.
Static default– it sends data to unknown destination + specified n/w.ex in isp we can have different connections. It uses 0.0.0.0 as the address for connection. Symbol of static default is s*.
- Dynamic route
It will choose the path by itself. Paths are found by the routing protocols.
Chooses the best or main path. If that path fails, it will find out the next alternate path. Routing protocols like RIP/EIGRP/OSPF decide the paths.
Q#8) Differentiate User Mode from Privileged Mode
User Mode is used for regular task when using a CISCO router, such as to view system information, connecting to remote devices, and checking the status of the router. On the other hand, privileged mode includes all options that are available for User Mode, plus more. You can use this mode in order to make configurations on the router, including making tests and debugging.
Q#9) What are the conversion steps of data encapsulation?
Conversion steps of data encapsulation includes
- Layer one, two and Three ( Application/presentation/session) : Alphanumeric input from the user is converted into Data
- Layer Four (Transport): Data is converted into small segments
- Layer Five (Network): Data converted into packets or datagrams and Network header is added
- Layer Six (Data Link): Datagrams or packets are built into frames
- Layer Seven (Physical): Frames are converted into bits
Q#10). What are the functions of CDP?
Answer: CDP is used for Cisco Discovery protocol that is a layer 2 protocols and works on the basis of MAC address. It is also used to find the adjacent Cisco devices. It can be used to find out port numbers, iOS details, IP addresses, switch models, router models, interface details and device ID.
Q#11). Can you differentiate half duplex and full duplex?
Answer: In half-duplex, the communication will occur only in one direction while the communication will occur in both the directions in full duplex. It is one of the important CCNA interview questions that you should know during the preparation for the interview.
Q12). What do you mean by latency?
Answer: Latency is considered the amount of time delay. It can be measured as the time difference between the time when the network will receive data and when it will be sent by another network.
Q13) What is MTU?
Answer: MTU is used for maximum transmission unit. This term is used for the maximum packet size that will be sent on the data line without the requirement of fragmentation. It may be one of the important CCNA routing and switching interview questions and answers that you should know.
Q14. What is the difference between ‘cross cable’ and ‘straight cable’?
Ans. Cross cables are used to connect same group devices while straight cables are used to connect different group devices.
Q#15. At which layer of OSI does frame relay technology work?
Ans. At data link layer.
Q#16. What is the size of a Cisco ping packet?
Ans. The size of a Ping packet in Cisco by default is 100 bytes.