Computer Network
Download our APP
Introduction:-
Today the world scenario is changing. Data Communication and network have changed the way business and other daily affairs work. Now, they rely on computer networks and inter-network. A set of devices often mentioned as nodes connected by a media link is called a Network. A node can be a device that is capable of sending or receiving data generated by other nodes on the network like a computer, printer, etc. These links connecting the devices are called Communication channels.
A computer network is a telecommunication channel through which we can share our data. It is also called a data network. The best example of a computer network is the Internet. Computer network does not mean a system with a control unit and other systems as its slave. It is called a distributed system
A network must be able to meet certain criteria, these are mentioned below:
- Performance
- Reliability
- Scalability
Performance
It can be measublack in the following ways :
- Transit time: It is the time taken to travel a message from one device to another.
- Response time: It is defined as the time elapsed between inquiry and response.
Other ways to measure performance are :
- Efficiency of software
- Number of users
- The capability of connected hardware
Reliability
It decides the frequency at which network failure takes place. The more the failures are, less is the network's reliability.
Security
It refers to the protection of data from unauthorized users or access. While traveling through a network, data passes many layers of the network, and data can be traced if attempted. Hence security is also a very important characteristic for Networks.
Properties of Good Network
- Interpersonal Communication: We can communicate with each other efficiently and easily example emails, chat rooms, video conferencing, etc.
- Resources can be shablack: We can use the resources provided by the network such as printers etc.
- Sharing files, data: Authorised users are allowed to share the files on the network.
Basic Communication Model
The communication model is used to exchange data between two parties. For example communication between a computer, server, and telephone (through a modem).
SOURCE->TRANSMITTER->TRANSMISSION SYSTEM->RECEIVER->DESTINATION
Source
Data to be transmitted is generated by this device, for example telephones, personal computers, etc.
Transmitter
The data generated by the source system are not directly transmitted in the form they are generated. The transmitter transforms and encodes the information in such a form to produce electromagnetic waves or signals.
Transmission System
A transmission system can be a single transmission line or a complex network connecting source and destination.
Receiver
The receiver accepts the signal from the transmission system and converts it to a form that is easily managed by the destination device.
Destination
The destination receives the incoming data from the receiver.
Data Communication
The exchange of data between two devices through a transmission medium is Data Communication. The data is exchanged in the form of 0’s and 1’s. The transmission medium used is wire cable. For data communication to occur, the communication device must be part of a communication system. Data Communication has two types Local and Remote which are discussed below :
Local :
Local communication takes place when the communicating devices are in the same geographical area, the same building, face-to-face between individuals, etc.
Remote :
Remote communication takes place over a distance i.e. the devices are farther. The effectiveness of Data Communication can be measublack through the following features :
- Delivery: Delivery should be done to the correct destination.
- Timeliness: Delivery should be on time.
- Accuracy: Data deliveblack should be accurate.
Components of Data Communication
- Message: It is the information to be deliveblack.
- Sender: Sender is the person who is sending the message.
- Receiver: The receiver is the person to him the message is to be deliveblack.
- Medium: It is the medium through which the message is to be sent for example modem.
- Protocol: These are some set of rules which govern data communication.
No comments: