Using ICT systems

The computer

Using ICT systems

Computers in an ICT System

• Multiple computers, usually with username and password entry

• Looking after them – – Shutting down properly to prevent data

corruption.– Looking at system settings and user

preferences.

Using ICT systems

Computers in an ICT System

• Interfaces – Command line

• Type precise instructions• Hard to use

– Menu driven interface• Choice through number or letter

– GUI• Graphical user interface – windows.

Using ICT systems

Computers in an ICT System

• Graphical User Interface.– Can be customised

• Adjusting window size• Mouse settings• Icon size• Screen resolution• Desktop fonts• Colour• Position• Graphics• Contrast• Volume• Toolbars• Date and Time

Using ICT systems

Computers in an ICT System

• Folder structures– Important to have a proper sensible

folder structure for your files with sensible file names.

Using ICT systems

Networking

Using ICT systems

What is a network?

• Two or more computers that are linked together

• So that they are able to share resources (data, programs, services (e.g., the Internet) and hardware)

Using ICT systems

Peer-to-peer networks

• Each computer on the network is of equal status

• All computers share each other’s resources

• Simple to set up• Only suitable for

small networks

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Client-server network

• A more powerful computer, called the server, is in charge of the network

• Software and data is stored on this server

• They are complex to set up• They are ideal for larger networks

Using ICT systems

LANs and WANs

Local area networks:• Confined to a small area • Usually located in a single

building • Use cable, wireless,

infrared and microwave links that are usually owned by the organization

• Cheap to build• Cheap to run

Wide area networks:• Cover a wide geographical

area (e.g., between cities, countries and even continents)

• In lots of different buildings and cities, countries, etc.

• Use more expensive telecommunication links that are supplied by telecommunication companies

• Expensive to build• Expensive to run

Using ICT systems

The components of networks

• Data transfer medium• Network card (also called network

interface card)• Hubs, switches and routers• Network software

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Data transfer medium

The medium/method by which the data is transmitted in a network can be:•metal wire•fibre optic cable•wireless

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Communication devices 1

A network card:• prepares data for

sending over the network

• sends the data• controls the flow of

data

Using ICT systems

Communication devices 2

A hub:• is used to join

computers in a network

• allows the connection of cables

• allows sharing files and Internet access

Using ICT systems

Communication devices 3

A switch:• similar device to a hub

but more intelligent• can look at a packet of

data to decide where it should go

• reduces the number of packets of data on a network which speeds the network up

Using ICT systems

Communication devices 4

A router:• can be wired or

wireless• is used to join

several networks together

• is often used to connect several computers in the home to the Internet

Using ICT systems

Networking software

Consists of:• Network operating systems – specialist

operating systems designed specifically for networks

• Network management software – used to help a network manager run a network by keeping track of software, keeping software up-to-date, installing software security patches, helping to manage the help-desk, etc.

Using ICT systems

Advantages of Networks• Share hardware• Software installed in one place on client-

server networks• Improved security• Speed• Costs reduced with network versions of

software• Email facilities• Central stores of data

Using ICT systems

Disadvantages of Networks• Needs network manager

• Security problems such as viruses spread quickly.

• Breakdowns• Infrastructure can be expensive