Hello guys, 🙋♂️
I hope you are doing well.
I’m back with another topic. And if you find my blog helpful please let me know. So now let’s begin…
What are Computer networks?
The computer network is a set of computers that are connected together so that they can share information and resources.
What Do Networks Do?
- Sharing information
- Communication like email, video, instant messaging e.t.c
- Sharing resources such as printers, scanners, and photocopiers
- Sharing files and media
- Sharing software and operating programs on remote systems
- Allowing network users to easily access and maintain information
Basic characteristics of Computer networks
- Fault tolerance: It is the ability of connected devices in the network to continue their functions after the failure of any device without any interruption.
- Scalability: It is the ability to continue to function well when it is changed in size or volume in order to meet a user's need. Typically, the rescaling is to a larger size or volume.
- Quality of service (QoS): Quality of service (QoS) refers to any technology that manages data traffic to reduce packet loss, latency, and delay in sending data packets over a network.
- Security: Protection of data over network and prevention from unauthorized access.
What is Data Communication?
Data communication is the exchange of data between two nodes via any transmission model.
- Data Flow: Data flow shows the transfer of information from one part of the system to another.
- Simplex: In this type of data flow one device can transmit data and another device will receive i.e. Communication is always unidirectional.
- e.g. mouse, joystick, keyboard, and so on
- Half-duplex: In this data can be transmitted by both devices but not at the same time i.e. one will transmit data and the other will receive. e.g. walkie — talkie
- Duplex /Full duplex: In full-duplex data can be transmitted bi-directionally at the same time. e.g. telephone
What are Protocols?
Protocols or rules govern all methods of communication.
All communication schemes will have the following things in common.
- Sender or source
- Receiver or destination
- Media or Channel
Protocols of Human Communication
- There must be a sender and a receiver.
- Comfortable language should be used.
- Speed and time of delivery of communication.
- Confirmation of delivery
Protocols of Network Communication
- Message encoding: Primarily messages are converted into bits by the sending hosts. Each bit is encoded into a form of sound, light waves, or electrical impulses depending on the network media. The receiver receives and decodes the signal to understand. Encoding between hosts must be in a proper format for the medium.
- Message formatting and encapsulation: There is an agreed-on format for the delivery of the message so that it could be delivered to the appropriate receiver.
- Message timing
a) Access method Host of the network should know when to start sending messages and how to deal with clashes.
b) Flow control Source and destination hosts use flow control to negotiate correct timing to avoid overwhelming the destination and ensure information is received.
c) Response timeout Host on the network have rules that specify how long to wait for responses and what action to take if a response timeout occurs.
- Message size: Long messages should be broken into pieces so that messages could travel over the network easily.
- Message delivery options
Unicast Data is sent to only one receiver of the network i.e. one to one delivery.
Multicast Data is sent to some of the receivers of the network i.e. one to many deliveries.
Broadcast Data is sent to all receivers of the network i.e. one to all delivery.
Peer to Peer Network
- No centralized administration
- All peers are equal
- Simple sharing application
- Not scalable
Peer to Peer Network
- No centralized administration
- All peers are equal
- Simple sharing application
- Not scalable
Client-Server Network
- Centralized administration
- Request-Response Model
- Scalable
- The server may be overloaded
Stay tuned. I will take this further and if you also post blogs please drop a link to your blog. I would love to read them. Thank You!
