Prepare for these system administrator interview questions

Computer Hardware and Networking Interview Questions

Hardware / February 2, 2017

Hardware and NetworkingHardware networking professionals are in­ demand across various sectors in India. From our records, hardware networking courses are finding an increasing number of takers from the student community. The number of hardware networking job opportunities for freshers is expected to grow extensively in the coming years.

For freshers, we understand interviews are always stressful. So in this article we have
covered interview questions with their answers. We have covered very importantly and common questions along with answers that were asked by our interviews.

Hardware & Networking Basic Interview Questions and Answers for Freshers

Q. What is a node and links?

A. In a network the devices at different endpoint located at a different location are called nodes
and the physical communication medium they using is called links.

Q. What are the layers of the OSI reference model?

A. There are 7 OSI layers:
1. Physical Layer
2. Data Link Layer
3. Network Layer
4. Transport Layer
5. Session Layer
6. Presentation Layer
7. Application Layer

Q. Describe Domain Name System

A. There are two types of client/server programs:
● First is used directly by the user, such as e­mail
● Second supports other application programs
The Domain Name System (DNS) is a supporting program that is used by other programs
such as to find the IP address of an e­mail recipient.

Q. What are the difference between Domain and Workgroup?

A. Find the difference between domain and workgroup:
Domain:
● Server is responsible for data safety
● Centralize administration
● Main aim is to secure data
● Best suite in company environments
Workgroup
● Every PC is responsible for its own security
● No centralize administration
● Main aim to save hardware resource
● Best suite in the school, training institute, cyber cafe

Q. Define Fully Qualified Domain Name and Partially Qualified Domain Name

A. In hierarchical namespace, names are defined in an inverted­tree structure with the root at
the top. The tree can have only 128 levels: level 0 (root) to level 127. Each node in the tree
has a label, which is a string with a maximum of 63 characters. The root label is a null string
(empty string). In this tree, all the labels have a different name, which guarantee the uniqueness
of the domain names. A full domain name is a sequence of labels separated by dots (.). The
domain names are always read from the node up to the root.
● Fully Qualified Domain Name
If a label is terminated by a null string or empty string, it is called a fully qualified domain name
(FQDN).
● Partially Qualified Domain Name
If a label is not terminated by a null string, it is called a partially qualified domain name
(PQDN). A PQDN starts from a node, but it does not end with the root.

Q. Describe attenuation, distortion, and noise in brief

A. Attenuation: When a signal travels through a medium, it loses some of its energy due to
resistance of the medium. This loss of energy is called the Attenuation. This is the reason why a
wire carrying electric signals gets warm. Some of the electrical energy in the signal is
converted to heat. To overcome this problem, amplifiers are used to amplify the signal.
Unit of the decibel is used to find out if a signal has lost or gained strength. The decibel (dB)
measures the relative strengths of two signals or one signal at two different points. If decibel
is negative then a signal is attenuated and if the positive signal is amplified.
Formula:
Where PI and P2 are the variable and the powers of a signal at points 1 and 2, respectively.
● Distortion
When the signal travels through the medium from one point to another it may chance to
change the form or shape of the signal. It is called distortion. Distortion can occur in a composite
signal made up of different frequencies. Each signal component has its own propagation
speed through a traveling medium and, therefore, its own delay in reaching the final
destination. Means signal components at the receiver have phases different from what they
had at the sender.
● Noise
The third cause of impairment is Noise. Following types of noise are possible.
➢ Thermal noise.
➢ Induced noise.
➢ Crosstalk noise.
➢ Impulse noise.
This noise may corrupt the signal.
Thermal noise is produced due to the random motion of electrons in a wire which creates an
extra signal not originally sent by the transmitter.
Induced noise comes from sources such as motors and other electronic appliances. These
devices act as a sending antenna, and the transmission medium acts as the receiving
antenna.
Crosstalk is the effect of one wire on the other.
Impulse noise comes from power lines, lightning etc.

Q. What is IP?

A. An Internet Protocol address (IP address) is a numerical label assigned to each device
(e.g., computer, printer) participating in a computer network that uses the Internet Protocol for

Source: www.jetking.com