Understand computer networks, including the Internet; how they can provide multiple services, such as the World Wide Web, and the opportunities they offer for communication and collaboration
This is a challenge because most of us have not thought about how these ever-present technologies do what they do.
Computer networks, including the Internet, are made up of computers connected together. The computers include fast, dedicated machines that pass on data that’s not intended for them (called ‘routers’, ‘gateways’, ‘hubs’ or ‘switches’, depending on particular roles), and ‘servers’ (always-on machines looking after emails, web pages and files that other computers might ask for from time to time). The connections between the computers in a network may consist of radio or satellite signals, copper wires or fibre-optic cables.
Information stored on computers and information travelling over networks must be digitised (i.e. represented as numerical data). The computer network in your school and the Internet use the same method or ‘protocol’ to send and receive this data. The data is broken up into small ‘packets’, each with identifying information, which includes the IP (Internet protocol) address of the sender and recipient.
These packets of information make their way across the Internet from source to recipient. At the far end, the packets get stitched back together in the right order and the email is delivered, the website is accessed, or the Skype call gets connected. Many of these packets, travelling at near light-speed, are generated by web servers returning web pages to the browser requesting them.
By connecting people around the world and passing on packets of data from sender to recipient, the Internet has created many opportunities. These range from communication (such as email, video conferencing, blogs, forums, social networks) and collaboration, such as wikis (including Wikipedia), to real-time collaborative editing, Creative Commons media (permission to share and use creative work with conditions stated by the creator) and open-source software, which is available for us to use and change.
