• सुखार्थी त्यजते विद्यं विध्यार्थी त्यजते सुखम्सु sखर्थीन: कुतॊ विद्या कुतॊ विध्यार्थीन: सुखम् ||
  • “Luxury people leave knowledge, but a student leaves Luxury No knowledge for one who seeks Luxury, No luxury for student”
  • न चोर हार्यं न च राज हार्यं न भात्रू भाज्यं न च भारकारि |व्ययं कृते वर्धत एव नित्यं विद्याधनं सर्वधनप्रधानम ||
  • Cannot be snatched away by thief, cannot be snatched away by king, Cannot be divided among brothers, Not heavy either If spent daily, it always keeps growing. The wealth of knowledge is the precious of wealth of all”

Introduction to computer networks.

Introduction to computer Network

The term ''Computer Network'' is a collection of autonomous computers interconnected by a single technology. Two computers are said to be interconnected if they are able to exchange information.

It is a set of computers connected together via communication media for the purpose of sharing of resources

The resources which can be shared are software, hardware, and data. e.g. a computer network can share files, folders, application software , hardware like printer, scanner, web camera etc.

Characteristics of a Computer Network

A network must meet following criteria:

1           Performance

2           Reliability

3           Energy Efficiency

4           Security

5           Scalability

6           Fairness

7           Adaptability

8           Channel Utilization

9           Throughput


Performance can be measured in following ways:

A.   Transit Time: Time taken by the message to travel from one device to another device.

B.   Response Time: It is the elapsed time between the enquiry and response.

Performance of a network depends upon:

Capability of Software

Efficiency of Hardware

Number of users

Type of transmission media used


A.   It is the frequency of network failure. More is the failure less reliable is the network.

B.   It is the measure of time taken by the network to recover from the failure.

C.   It also defines the robustness in a catastrophe. (disaster or misfortune)

3.Energy Efficiency:

Energy Efficiency refers to the energy consumed per unit of successful communication.


Network security issues include:

A.   Protecting data from unauthorized user or access.

B.   Protecting data from damage and implementing policies and procedures for recovery from and data losses.

5. Fairness:

Fairness refers to the ability of different systems to equally share a common transmission channel


Adaptability refers to the ability to accommodate the changes network topology.

7.Channel Utilization:

Channel utilization refers to the bandwidth utilization for effective communication.


Throughput refers to the amount of data successfully transferred from a sender to a receiver in a given time.

9. Scalability:

Scalability refers to the ability to accommodate the change in network size.

Related Question

Q1.    Define Computer Network. What are certain criteria that a computer network should meet?     [10 marks]