Basic Concepts:
The Internet began In 1969, As an experimental four-computer network called ARPAnet (The Advanced Research Projects Agency Network), which was designed by the U.S Defense Department so that reaserch Scientist could communicate. In approximately two years, ARPAnet grew to about two-dozen sites and by 1981, consited of more than two hundred sites.
In 1990, ARPAnet was officially disbanded and the network, which now consisted of hundreds of sites, came to be known as the internet.
After a while, commercial organization began to recognize the use of such a network which converted the whole world into a Global Village and allowed almost instant access to business or commerce data and a host of other services such as e-mail and e-commerce.
The rapid growth of the internet was due to networking giants like British telecom, Hyundai, AT&T and others setting up fast and reliable networks that encircled the globe.
The networking giants were very clear about their role.
This was to setup and maintain, monitor and expand existing networks.
Hence another layer was formed above this layer called ISP's (internet service providers).
The networking giants gave access to the internet via Gateways.
Using ISP gateways it is perfectly possible to route business or commerce data from one point of the globe to another by using a heterogeneous mix of networks owned by different networking giants who have worked out an aggreement between themselves on the costs of usage.
ISP's in turn offer clients' access to the internet via their gateways ass paid for service.
An ISP's gateway generally consists of a server with a permanent connection to the internet.
The server's connection to the internet is called it's internet pipeline.
Special hardware is used as the pipeline to connect an ISP's server to the internet.
ISP pipe line bandwidths of 2GB to 10GB are quite Common.
Multiple pipelines can be purchased by an ISP from a networking giants and Used.
Clients that log into the internet via an ISP Commonly use only 33.6 kilobytes of the ISP's bandwidth.
Occasionally a client whose data traffic is very high will use special connectivity methods (ISDN) to an ISP's server and use between 64 Kbps to 128 Kbps of the ISP's bandwidth.
If a client has huge data traffic then a client could directly negotiate with a networking giant to have it's own private Gateway to the internet and then make use of huge bandwidth for its data transfer.
These types of clients are not ISP's and as a general rule do not allow other clients access to their gateway.
Even in such casue physical access to the internet is a server.
The structure:
NETWORK BACKBONE( HYUNDAI, AT&T, BRITISH TELECOM):
10GB - INTERNET SERVICE PROVIDERS (ISP's) <=> client A, client B, client C.
BACKBONE:
10GB - DIRECT ACCESS BY MNC's <=> Branch A, Branch B.
Network:
10GB - INTERNET SERVICE PROVIDERS <=> Client A, Client B.
The Internet consists of two types of computer servers and clients
- Computer which offer information to be read are called Servers
- Computer that read the information offered are called clients
Servers run special software (Web Server software) that allows them to
- Respond to client requests for information
- Accept data from clients
Some of the most popular software which servers run to allow them to respond to client requests for information is , internet information server ( IIS ), Apache Web server, microsoft personal web server.
Clients run special software ( browser software) that allows them to
- Locate the appropriate server
- Query the server for the information to be read some of the most popular browser software that clients run, to allow them to query internet Servers for information are Netscape Communicator, Internet Explore.
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