Home and Personal Communications How computers connect to the Internet Computing Department1

The Internet No innovation in recent years has had more impact on the way we live than the Internet It has changed the way we perform daily tasks forever But what is it? “The Internet is a global network of computers that can communicate with each other (i.e send and receive data)” Computing Department2

How computers connect to the Internet Any computer can connect as long as they have the correct hardware and software, but you also need an ISP (Internet Service Provider). An ISP has powerful computers called servers which are permanently connected to the Internet Most ISP charge for their services Other software needed is a browser such as Internet Explorer. Computing Department3

How computers connect to the Internet Computers can connect to the Internet in a number of ways: Computing Department4 Dial Up Broadband Cable – Fibre Optic Satellite Mobile Comms (4G/Wifi) Tethering

Dial-Up Internet Dial up internet is an extremely slow internet connection. 56kbps (roughly 0.5mpbs). Requires a phone-line and a modem on your computer. Dial’s your ISP to make a connection. Converts signal into one that can be passed down a phone line Cheap Not suitable for downloading music etc (an average song would take around 1-2 hours to download!) Computing Department5

Satellite Internet Useful for users where standard internet (broadband / cable) is not available such as rural areas where cables cannot be laid Available world-wide Some delay when using the connection, making it a bit “laggy / jumpy.” Not suitable for online games or advanced use like “remote surgery” Suffers from “rain fade.” Signal deterioration from moisture. Computing Department6

Broadband Fast connection via ISDN and ADSL ISDN has been replaced generally by ADSL (Asymmetric Digital Subscriber Line) which uses a nationwide network of digital connections. This system uses digital signals compatible with computer signals so there is no need for a modem ADSL uses existing phone lines to connect. Can use phone at same time as connection to Internet Can use webcam services Watch video/listen radio in real time Several devices can connect at same time Computing Department7

Cable Fibre optic cables provide broadband as well as TV and telephone Generally faster than ADSL Reliable Constant high speed link Expensive Computing Department8

Mobile Communications Wi-Fi Computing Department9

Mobile Communications Wi-Fi Allows you to share a broadband connection. No need for lots of wires. Can access the web on a range of appliances (phone, TV, games console etc). Let’s everything ‘talk’ to each other. Secure (if protected) Requires wireless equipment. Can ‘conflict’ with surrounding devices. Could be hacked? Security / Transmission interception. Wireless Router Needed. Can share information, music etc. Hot spots Computing Department10

WI-FI Advantages: – Not restricted where you work – Work on the move – No wires – Many Devices can connect Disadvantages: – Can be less secure/hackers – Black spots & Limited to distance from source of transmission Computing Department11

Bluetooth Method used to transfer data over short distances from fixed/mobile devices Uses Radio Chips Uses little power. Instant configuration. Simply scans and find a name. Enter a pin to securely connect. No in-line of sight. You do not have to be sat next to someone. Computing Department12

Bluetooth Any device can communicate together if they have Bluetooth. Relatively slow connection of 1Mbps, compared to infra-red. Bluetooth can open the door for security breaches, once access is granted. Potential for transmission to be intercepted. Illegal transmissions (music etc) Computing Department13

Bluetooth Uses: – Wireless keyboards and mice – Wireless headphones – Printing – Wireless headsets – Games like the Wii Computing Department14

Bluetooth Advantages: Speed: Can send/receive data/images/music/text instantly. Cost: Can send/receive data/images/music/text for no extra cost. No wires are needed/wireless. You can synchronise devices/link devices. Hands free (while driving). Security: Pairing requires PIN. Disadvantage: Can only be used over short distances. Relatively small bandwidth / slow to transfer large files. Cannot send to a group / can only handshake with one device at a time. Runs battery down quickly. Can be used for hacking. Computing Department15

Mobile Communications 3G /4G – Accessing the internet / using data connection via mobile technology. – Can be via mobile phones. Can be on computer using a USB ‘dongle’ often provided by phone providers. Computing Department16

G.I.S “A Geographic Information System (GIS) is a collection of computer hardware, software and geographic data used to analyse and display geographically referenced information.” Put simply: – A system which combines a geographical map, along with additional information, such as: Facilities in that area. Buildings / landmarks. Speed / traffic information Optimal routes when driving. Computing Department17

Mobile Phone applications Computing Department18

Satellite Navigation Computing Department19

Google Earth Computing Department20

Other examples: Multimap AA route finder Computing Department21

GIS Advantages Can select / plan the shortest route from A-Z / real time guidance of route Can share position with others Can see bird’s eye view of your house Can be found by others if lost/in an emergency Can track / be tracked / locates where you are Can find places of interest / petrol stations, etc. Can locate exactly where your photos have been taken Locate your device Can locate weather for your particular area / Can predict weather more accurately Online mapping / look at maps Walking tours Disadvantages: Can send you down a route you would not normally drive/ too narrow Can be difficult to use/get used too Data can be out of date/has to be updated Can cause accidents if input information whilst driving and become distracted Problems with loss of Satellite signal Drains battery quickly Computing Department22