Networks

Networks

1. Internet

   • A group of inter-connected networks, which can be used to communicate with other computers universally.

2. Networks

   • A group of two or more computer system which are inter-linked.

3. World Wide Web

   • An information system on the Internet which allows documents to be connected to other documents by hypertext links, enabling the user to search for information by moving from one document to another.
   • A collection of web pages
   • Stored on computers all over the world
   • Accessed via the Internet
   • No central storage
   • No owner

4. URL

   • Short for Uniform Resource Locator
   • A URL is a web address
   • All web addresses are unique

5. Parts of a Web Address

   • www.abc.co,uk/images/logo.jpg
     • www = World Wide Web
     • abc = Name of organisation
     • co = A company
     • uk = UK-based
     • images = folder location
     • logo.jpg = file name

6. Domains

   • Top Level Domains (TLDs)
     • .uk
     • .fr
     • .es
     • .de
     • .cz
     • .com
     • .org
     • .gov
     • .edu

7. HTTP

   • Short for Hyper Text Transfer Protocol
   • A protocol is a set of rules
   • HTTP defines the rules used by web browsers and servers to exchange information

8. Connectivity

   • bandwidth = amount of data that can be transferred at once/speed of data transfer (Mbps)
   • broadband = high speed connection to the Internet large bandwidth
   • Download is faster than upload, because mostly people download things on the Internet more than they upload things.
     • In the school, upload speed is higher than the download speed because many people are uploading things (eg setting homework, submitting homework etc.)
   • Fibre optic cables
     • Data travels through these at a speed of 299 792 458 m/s, which is the speed of light
     • copper cables
       • A lot of interference
       • much cheaper than fibre optic cables
       • average broadband connection
     • almost 0 interference, due to lack of friction
     • much faster for transmission
   • wireless
     • cheap
     • easy to set up
     • allows you to link devices
     • you can access anything anywhere
     • less secure than cabled data transfer
       • interference
     • not available in some places
     • slower
   • buffer
     • an area of storage