Network Concepts
1.
A computer network is a set of computers or devices that are connected with each other to carry on data and share information. In computing, it is called a network as a way to interconnect two or more devices to each other using cables, signals, waves or other methods with the ultimate goal of transmitting data, share information, resources and services.
The purpose of a network is, generally, to facilitate and expedite communications between two or more instances on the same physical space or connected remotely. Such systems also allow cost savings and time.
2.
A computer network can serve several distinct purposes:
- Sharing resources (files, applications or hardware, an Internet connection, etc.)
- Communication between people (email, live discussions, etc.)
- Communication between processes (such as between industrial computers)
- Guaranteeing full access to information for a specified group of people (networked databases)
- Multiplayer video games
3.
The most known type of network is the Intranet, which is a private network that uses Internet as a basic architecture in order to connect various devices. Internet, however, is a technology that connects devices throughout the world, and that is why it is called “network of networks.”
4.
The networks are classified by range (personal, local, campus, metropolitan or wide area), as well as by method of connection (cable, fiber optics, radio, infrared, wireless, etc..) or by functional relationship (client – server or peer-to-peer). Also in the topology field there is a clasification to be aware of (bus, star, ring, mesh, tree etc.) and directional (simplex, half duplex or full duplex).
5.
there are two main types of the computer networking client-server and peer to peer. In the client server computing, a computer plays a major role known as server, where the files, data in the form of web pages, docs or spread sheet files, video, database & resources are placed. All the other computers in the client/server networks are called clients and they get the data from the server. In the peer to peer networks all the computers play the same role and no computer act as a centralized server. In the major businesses around the world client-server networks model is in major use.
6.
A network topology defines the structure, design or layout of a network. There are different topologies like bus, ring, star, mesh, hybrid etc. The star topology is most commonly used topology. In the star topology, all the computers in the network are connected with a centralized device such as hub or switch. Thus forms a star like structure. If the hubs/switch fails to work for any reason then all the connectivity and communication between the computers will be halted.
7.
A common communication language is used by the computers and the communication devices is known as protocols. The most commonly used and popular protocol on the internet and in the home and other networks is called TCP/IP. TCP/IP is not a single protocol but it is a suite of several protocols. A computer network can be a wired or wireless and TCP/IP protocol can work both in types of a network.Data flow or communication can be divided into seven logical layers called OSI layers model that was developed by Intel and Xerox Corporation and was standardized by ISO.
8.
The Open System Interconnection (OSI) reference model describes how information from a software application in one computer moves through a network medium to a software application in another computer. The OSI reference model is a conceptual model composed of seven layers, each specifying particular network functions. This is a seven layered design that depicts the typical network architecture and a conceptual framework for communication and how data can pass through one layer to another in such an architecture, the protocols involved, etc.
9.
The OSI model describes the following seven layers in its architecture:
1. Application layer
2. Presentation layer
3. Session layer
4. Transport layer
5. Network layer
6. Data Link layer
a. Media access control sub-layer
b. Logical link control sub-layer
7. Physical layer
I hope it will be use ful
