Where did the Internet come from?
Alarmed at what the consequences of magnetic pulses from a nuclear blast might be on an
increasingly computer-controlled communications infrastructure, in the late 1960s the US
military began to develop a 'headless' computer network. This would be, in theory at
least, indestructible - since it had no 'Central Control', it could continue to exist even
if component parts suffered damage. Together, academic institutions and the military
began to develop the network of cables and computers which formed the early backbones of
the Internet.
This merely provided the physical connections between computers. Still to be developed
were the 'protocols' which allowed one computer to 'talk' to another.
It was all an extension of the filing system: you can get a computer to 'look' at the
files you have on your own computer. So, why not also the files on any computer to
which you can connect?
These protocols became the foundation of Internet and later, the World Wide Web.
In the early days, physicists used the Internet to talk to each other about physics...and
then inevitably, other things like Star Trek. The Internet was used for chat, email
and to send pictures - any electronic data that could be exchanged.
At that time, the Internet was not envisaged as a business application or even
a business-like environment.
(Which explains a lot about why it is so chaotic!)
Before we go any further, let's just take a minute to define some terms:
| Glossary of Ubiquitous Internet
Terminology |
| URL |
Universal Resource Locator - an Internet address. Web
sites are usually given in these terms. |
| HTTP |
Hypertext Transfer Text Protocol - the system used
by one computer to 'look' at files on another's. |
| FTP |
File transfer protocol - the system used to send or
download a file or program to any computer which you can reach |
| Firewall |
An electronic block between a computer and the outside
world. A whole network of computers can be protected from prying eyes with such a
firewall. |
| DNS |
Domain Name Server - this takes the domain name the
browser has requested e.g. www.here.com and translates
it into the correct IP address (a number like 191.200.13.2) |
|
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Internet, intranet and extranet
First there was the Internet; the networked computers exchanging data by HTTP. This is
where one machine's browsers asks of another machine on the Internet - for example: 'Hello
computer Joe90 at British Steel. Let me see a file called 'contacts.htm' which is located
in the directory 'Webpages/files/'
Then increasingly, organisations began to use the same system for networking their own
information.
It all looks the same - Web pages on a browser.
| Term |
Who has access? |
Example |
| Internet |
Through Internet service providers, anyone |
My computer in Oxford looks at Yahoo in San Franscisco |
| Intranet |
People whose machines are physically connected to a
network, or through authentication methods which recognise a machine as 'friendly' |
You, at your desk in Agchem R & D, look at another
file in Agchem, all behind a secure firewall. (If you are on my machine in Oxford, you
can't look at these files) |
| Extranet |
Through the Internet, but access is restricted to
authenticated users |
Remote-working staff at home, browsing
password-protected files of the company |
What do Internet addresses mean?
As we've already discussed, the WWW is just an environment in which people share
electronic information. The browser is a tool to 'look' at this information.
Browsers work by asking to see a file and stating its given location.
The URL (e.g. http://www.here.com/look_here/this_file.htm) is an address
no more. In fact, the first part of the address (www.here.com) is the domain
name - and corresponds to a number like 191.200.13.2, which is the real
Internet address of the computer your browser is looking at. The rest of the address
(look_here/this_file.htm) tells your browser exactly where to look.
N.B. By a convention of HTML, when you type www.here.com
you are in fact asking to see the file index.htm at the domain www.here.com
Whether or not you can see a file at a URL you have requested, depends of whether you
have the right permission - the appropriate security clearance.
How can you tell you are 'on' the WWW, as opposed to within the
your company's Intranet?
If you are using Internet Explorer v4, the browser
tells you if you are in the 'local intranet zone' or if you are in the external
'internet'.
It works a bit like a phone number: the area code tells you where you are: look
in a public phone booth in Kensington and the prefix is 0171 - which tells you that
Kensington is in Central London.
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