Network :
A Network is a connection of two are more various components connect with each other either social network or computer network. and transform data from source to destination through some media either (wire or wireless). A vehicle to carry the data from node to node that vehicle is called Protocol.
Social Network :
Social Network :
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Social Network |
A social network is a social structure made up of a set of social actors (such as individuals or organizations) and a set of dyadic ties between these actors. The social network perspective provides a set of methods for analyzing the structure of whole social entities as well as a variety of theories explaining the patterns observed in these structures. the study of these structures uses social network analysis to identify local and global patterns, locate influential entities, and examine network dynamics.
Computer Network :
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Computer Network |
A computer network or data network is a telecommunications network that allows computers to exchange data. In computer networks, networked computing devices pass data to each other along data connections. The connections (Network links) between nodes are established using either cable or wireless media. the best-know computer network is the internet.Network computer devices that originate, route and terminate the data are called Network nodes. Nodes can include hosts such as servers and personal computers, as well as networking hardware. Two devices are said to be networked when a device is able to exchange information with another device.
Uses of network:
Network reduce the human power and make work faster. it reduce the coast and share data with reliable way.
- Resource Sharing.
- High reliability.
- Low cost.
- Scalability.
Resource Sharing:
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Resource Sharing |
The goal is to make all programs, resources, especially data available to anyone on the network without regard to the physical location of the resource and the user. It is an attempt to end the "tyranny of geography". For example: Printers, scanners which are expensive resources can be shared among many computers. That is printer is installed on a single machine which is networked and used by all machine connected to that network.
High Reliability:
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High Reliability |
Store the copy of data in two or three machines Example: All files could be replicated on two or three machines, so if one if them is unavailable due to say hardware failures, the other copies could be used. Also many CPU's means if one goes down the others may be able to take over its work, although at reduced performance. It finds extensively useful in military,banking,air traffic control, nuclear reactor safety and many other applications, where the ability to continue operating in the face of hardware problems is of utmost importance.
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Low cost |
Storing a files is cost factor. If any file lost due to some naturals causes or human mistakes the work will start from begin it was a loss to an origination. also reduce the cost by purchasing a single server it is a ten times faster than personal computers. this is the fact that many system designers go for building systems where many personal computers are inter connected with this server(large machine). For single work can be done by multi users so the expenditure will reduce. Example: A project has to complete in 2 months. If we assign to a single person to complete this project it will take 4 or more moths to take while 4 persons can do this project in 1 month. so the cost on the project will save to an origination.
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Scalability |
It is the ability to increase system performance gradually as the workload grows just by adding processors. With main frames as server at some point of time the system is full, and it must be replaced by a larger one usually at great expense and even greater disruption to the users. With the client server model, new client and new servers can be added as needed without any disturbance to the users. That is the network can be expanded easily.
Networks to People:
In 1990's computer networks began to start delivering services to private individuals at home. These services are quite different from the corporate efficiency discussed in the above section. Below are few exciting uses for individuals.
- Access to remote information.
- Person to person communication.
- Interactive entertainment.
- Electronic commerce.
- Social issues.
Access to remote information:
There are many areas where access to remote information is necessary in our daily life. Here applications involve interactions between a person and remote database. One area seen is financial institutions like banks,power supply department etc. Many people pay their bills, manage bank accounts and handle investments electronically.
This was the site to pay power bill Online Bill Enquiry & Payment.
Person to person communication:
The facility like instant messaging drived from UNIX talk program allows two people to type messages at each other in real time. The multi person version of this idea is chat room in which a group of people can type message for all to see Another application is a peer to peer system.This was the sites to Chart Online Chart ,Enter chart room, etc.
Interactive entertainment:
The most common application is entertainment. It is huge and a growing industry. The major and widely used application is video on demand. It is possible to select any movie or television program in any country and have it displayed on individual screen instantly. New films becomes a more interactive, game playing, live television also becomes interactive, with audience participating in quiz shows, choosing among contestants, and so on. Now a days YouTube plays a major role in all type of videos like education, cinema etc.
This was the sites to watch videos Youtube,netflix,yahoo screen,dailymotion, etc.
Home shopping is already popular and enables users to inspect the online catalogs of thousands of companies. Some of these catalogs provide the ability to get an instant video on any product by just clicking on the products name. A customer can buy a product online. the customer can consult for any technical institutions. Many people paying their bills; manage bank accounts, etc online.
The widespread introduction of networking will introduce social, political problems. As long as like minded people have interactions with respect to technical topics or hobbies there will not be a problem now a days writing jocks on politicians, film industries, etc. The trouble comes when discussion is about favorite hero's, politicians, religion, etc. Views may be posted and messages is not limited to text, high resolution color photo graphics and even short video clips can be easily transmitted using computer networks.
This was the sites for social issues: facebook,twitter,linkedin,livejournal, etc.
Classification of computer networks:
There is no generally taxonomy accepted into which all computer networks fit. the computer networks are classified depending on transmission technology and scale.
Computer were also classified according to the Network layers at which they operate according to some basic reference models that are considered to be standards in the industry such as the seven layer OSI reference model and the four layers or five layers (some one say's four and some say five layers) TCP/IP model.
- By transmission techniques.
- By scale.
- By connection method.
- By functional relationship.
- By network topology.
- By services Provided.
- By protocol.
By transmission technique:
Computer networks may be classified as Broadcast or Point to Point networks.
By Scale :
To the scale or extent of reach of the network, for example as a personal area network(PAN), Local area network(LAN), Campus area network (CAN), Metropolitan area network(MAN), Wide area network(WAN).
By connection method :
Computer networks may be classified according to the technology that is used to connect the individual devices in the network such as home PNA, Power line communication, Ethernet, or Wireless LAN.
By functional relation:
Computer networks may be classified according to the functional relationships which exist between the elements of the network, for example Active networking, Client-Server and peer-to-peer(work group) architectures.
By network topology :
Computer networks may be classified according to the network topology upon which the network is based, such as Bus Topology, Star Topology, ring Topology, mesh Topology, Star-bus Topology, tree or hierarchical Topology network, etc.
By services provided :
Computer networks may be classified according to the services which they provide, Such as Storage area networks, Server farms, Process control networks, Value added network, wireless community networks, etc.
By Protocol :
Computer networks may be classified according to communications protocol that is being used on the network. Read the articles on list of network protocols and Protocol Stacks for more information.