CCNA Interview Questions and Answers
by Rupa.R, on Sep 10, 2022 4:13:03 PM
- Network Engineer.
- Network Administrator.
- Sr. Network Engineer.
- Information Technology (IT) Manager.
- Systems Administrator.
- Systems Engineer (Computer Networking / IT)
- Information Technology (IT) Director.
3. Which layer of the OSI model is responsible for reliable connections?
10. What do You Understand by Routing?
Routing is the process of taking Packet from source to final destination. Router is the device which does routing, which is based on destination ip address. Router does this process on hop by hop basis.
11. What is the difference between IGRP and RIP?
While IGRP evaluates factors like reliability, bandwidth, hop count and MTU to deduce and provide the best routing network, RIP solely relies on the hop numbers in order to know which route can best use for a network.
14. Name three fundamental differences between LANs and WANs.
Three fundamental differences between local-area and wide-area networks are:
LANs are limited to a small geographic area, such as a single building or small campus.
WANs cover a large geographic area, from citywide to worldwide.
LANs usually consist entirely of privately owned components. Some components of a
WAN, such as a packet switching network or point-to-point serial links, are usually leased
from a service provider.
A LAN provides high bandwidth at a relatively cheap price. The bandwidth across a WAN
is significantly more expensive.
15. What are the five layers of the TCP/IP protocol suite? What is the purpose of each layer?
The five layers of the TCP/IP protocol suite are the following:
Physical layer
Data link layer
Internet (or IP) layer
Host-to-host layer
Application layer
16. What is an address mask, and how does it work?
An IP address mask identifies the network part of an IP address. Each one in the 32-bit mask marks the corresponding bit in the IP address as a network bit. A zero in the mask marks the
Corresponding bit in the IP address as a host bit. A Boolean AND is performed in all 32 bits of the address and the mask; in the result, all network bits of the mask will be repeated, and all host bits will be changed to zero.
17. What is a subnet? Why are subnets used in IP environments?
A subnet is a sub grouping of a class A, B, or C IP address. Without subletting, the network part of a major class A, B, or C IP address can only identify a single data link. Subnetting uses some of the host bits of a major IP address as network bits, allowing the single major address to be “Subdivided” into multiple network addresses.
18. What is a redirect?
A redirect is an IP router function. If a device has sent a packet to the router and the router must forward the packet to a next-hop router on the same data link, the router will send a redirect to the originating device. The redirect will inform the device that it can reach the next-hop router directly.
19. What is the essential difference between TCP and UDP?
TCP, or Transmission Control Protocol, provides a connection-oriented service over the
Connectionless internet layer. UDP, or User Datagram Service, provides a connectionless service.
20. What mechanisms does TCP use to provide connection-oriented service?
Correct sequencing is accomplished with sequence numbers. Reliability is accomplished by using checksums, acknowledgments, timers, and retransmissions. Flow control is accomplished by windowing.