Difference between revisions of "The Internet"

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(What is the Internet)
(What is the Internet)
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==What is the Internet==
 
==What is the Internet==
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The Internet is an international Wide Area Network. It connects computers and networks over a large area.
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The Internet originates with the U.S. government's Advanced Research Projects Agency and was used for governmental and academic communication purposes. At this stage in the development it was used to send files and emails. After the issues of connecting packet switched networks was solved, the internet took a more recognizable form. By 1983 TCP/IP protocol was created and todays form of the internet was essentially formed.
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The term 'The Internet' was adopted in 1995.
  
 
==How is the Internet connected==
 
==How is the Internet connected==

Revision as of 12:04, 28 February 2017

What is the Internet

The Internet is an international Wide Area Network. It connects computers and networks over a large area.

The Internet originates with the U.S. government's Advanced Research Projects Agency and was used for governmental and academic communication purposes. At this stage in the development it was used to send files and emails. After the issues of connecting packet switched networks was solved, the internet took a more recognizable form. By 1983 TCP/IP protocol was created and todays form of the internet was essentially formed.

The term 'The Internet' was adopted in 1995.

How is the Internet connected

Router

A Router receives packets from a host or router and uses the destination IP address that they contain to pass on the packets to another host or router.

It would be impractical to connect hosts to other hosts, which is the main reason as to why we use routers. So that many hosts can connect to the router and then the router can connect to other networks.

Gateway

A Gateway is basically Donald Trump. It controls the wall between two different systems, for example on your home router to connect from your devices to the Internet. However, unlike the Donald, Gateways can translate. They translate the current protocols for the new system to understand. This allows two different systems with different protocols to be connected. Without this, data would be kept outside the border and could not communicate across it - welcome to Trump's America.

How is data transmitted

Packet Switching

Circuit Switching

The End to End Principle

The devices that are communicating should be the endpoints of the communication with no external input. The Internet serves as a medium to carry traffic between them but makes no changes the data involved. Therefore the transmitting devices control every aspect of the transmission, allowing security (through encryption) and the detection of errors, which maintains the integrity of transmitted data.

Using this principle allows the Internet to easily grow because there is no direct control over the number of endpoints.

URL

The Uniform Resource Locator is the standard address used to find a page, Web server or other device on the Web or Internet.

It specifies: How to access the server, ie which protocol to use Which server to access, ie the address if server What is to be accessed on the server, ie the path on the addressed server.

This was invented so that users could use a memorable name to refer to a network and a host on that network. Often the term 'Domain Name' is used instead of the correct term 'Full Qualified Domain Name' (FQDN). The domain name identifies one or more IP addresses. For example, the domain name "Microsoft.com" represents about a dozen IP addresses.

The DNS system is a hierarchy. A Domain Name Server accepts a Domain Name and returns the IP address associated with this Domain Name.

Domain Name

IP Address

Class 1

Class 2

Class 3

Domain Name Server

Internet Registrar

Internet Registries

Related Topics

Subnet Masks

Private - Public IP Addresses

IP6 vs IP4

DHCP

Network Address Translation

Port Forwarding