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Introduction to Computer Networks

ARPANET Networks and Internet

Network Topologies

Types of Network

OSI Model and Its Functions

Services and Protocols of OSI Model

Layering Architecture of Networks


Local Area Networks

Wide Area Networks

Introduction to Network Management

Introduction to Computer Networks

In computer network, we use two terms “Data communication” and “Networking”. Data communication and networking are changing the way we live. Why we wait for the report from Germany to arrive by mail when it could appear almost instantaneously through computer networks.  The development of personal computers brought about a tremendous change in business, industry, science and education. We can communicate from one place to another more efficiently using computer networks.

Data communication
Data communication is made up of two words “Data” and “communication”, where data refers to the information presented in whatever form is agreed and communication is a way through which we can exchange our information from one to another.
The exchange of data between two devices is known as Data communication which has some form of transmission medium such as wire cable. Data communication have four types: Delivery, Accuracy, Timeliness, and jitter.

  • Delivery
    With the help of this the data id delivered at correct destination. The data is not lost and corrupted.
  • Accuracy
    The Message or data is transmitted from one end to another that’s the delivery of data should be accurate.
  • Timeliness
    The system must deliver the data from source computer to destination computer on time.
  • Jitter
    Jitter refers to the variation in packet arrival time. It is the uneven delay in the delivery of audio or video packet.

There are five components of data communication:

Component of data communication
  • Message
    The message is the information to be delivered from sender to receiver. Information can be text, numbers, pictures, audio and video.
  • Sender
    The sender is the device that sends the information to the destination. It can be computer, workstation or telephone.
  • Receiver
    The receiver is a device that receives the data send by sender. It can be telephone, television.
  • Transmission Medium
    The transmission medium is a way through which we can send our information from sender to receiver. The physical path through which a message should travel.
  • Protocols
    A protocol is a set of information that governs data communication. It show an arrangement between the communicating devices.

Data Flow
We can use simplex, half-duplex, and full-duplex for communicated the devices.

  • Simplex Mode
    The communication is unidirectional in simplex mode. One of the two devices can be transmit at a time not both at a same time. For example: keyboard, monitor.
    Simplex mode
  • Half-duplex
    Each station can both transmit and receive the data but not at the same time in Half-duplex. When one device is sending the data the other one only receive and vice versa.
  • Full-duplex
    In full-duplex mode, both the transmitter and receiver can transfer the data simultaneously.
    Full - Duplex

A network is a set of devices (nodes) which connected by communication links. In a computer and in its devices node will be send or receive the data which is generated by different nodes on the network. There are two types of connections :

  • Point-to-point
    It is a kind of connection which provides a dedicated link between two devices. The entire ability is reserved for transmission between those devices.
    Point-to-point connection
  • Multipoint
    A multipoint (multidrop) connection is one in which more than two devices can be able to share single link.
    Multipoint Connection


#Things To Remember