A-Level IT: Digital Devices and Networks

What are multifunctional devices?

Devices that execute several tasks.

What are examples of multifunctional devices?

• Photocopiers

• Smartphones

• Laptops

• Desktop computers

• In-car entertainment systems

What makes a device digital?

If it is controlled by a microprocessor.

What are the advantages of desktop computers?

• Faster processors

• Easier to modify and upgrade

• Harder to steal (less portable)

What are the advantages of laptop computers?

• More portable

• Fewer compatibility issues with devices and hardware

• Batteries are usable if a power supply fails

What are servers?

Hardware units that provide services to other programs.

What types of servers are there?

• Mail servers

• Game servers

• File servers

• Printer/Print servers

• Database servers

• Web servers

What does GPS stand for?

Global Positioning System.

How is a GPS operated?

• 31 satellites orbiting the Earth send out time signals.

• Co-ordinates are calculated using the time taken for signals to reach devices.

What are some examples of data capture devices?

• GPS receivers

• Barcode scanners

• Automatic Number Plate Recognition (ANPR) cameras

• Debit/credit card readers

What are some examples of technology used for education?

• Virtual Learning Environments (VLEs)

• Massive Open Online Courses (MOOCs)

• Video learning

• Audio learning

• Commercial learning platforms (Udemy, Seneca, Show My Homework)

What factors should people consider when implementing new servers in an office?

Their budget, the servers’ reliability and the timescale for implementing them.

What are peripheral devices?

Input and output devices.

What input devices are present in self-driving cars?

• Lidars

• Radars

• High-resolution cameras

What output devices are present in self-driving cars?

• Motors

• Indicator lights

• Brakes

• Steering actuators

What are some features of optical media?

• Capacity

• Durability

• Reliability

• Portability

• Speed

• Cost

What are Personal Area Networks?

Networks set up between devices less than 10 metres apart.

How are Personal Area Networks connected?

Using Bluetooth and USBs.

What are Local Area Networks?

Networks that connect devices (nodes) together over small areas.

How are devices in Local Area Networks connected?

Using network switches.

How do wireless Local Area Networks connect to devices?

Using wireless access points.

What are Wide Area Networks?

Networks that span different regions and countries.

What factors should be considered when choosing what network to implement?

• Ease of use

• Security

• Fast internet access

• Compatibility of hardware and network equipment

• Accessibility

What is the purpose of operating systems?

To manage data, memory and running of tasks on a device.

What is manual data processing?

Manually entering information into a computer system.

What is automatic data processing?

When data is input and processed by a computer system.

What are optical disks?

Disks that store data on a spiral track running from the inside to the outside.

What is the capacity of a compact disk?

700MB.

What does EPOS stand for?

Electronic Point of Sale.

What are the properties of magnetic hard disks?

• Large capacity

• Quicker to access data

• Less durable

• Less portable

What are the properties of solid state hard disks?

• Similar capacity to magnetic disks

• More expensive per gigabyte

• Faster rate of data transfer

• More portable

• More reliable

• More durable

What are real-time operating systems?

Operating systems designed to make sure tasks are completed by a specific time.

What are single-user, single-task operating systems?

Operating systems on devices allowing only one user. They pause apps in progress to let others run if they are selected.

What are single-user, multi-tasking operating systems?

Operating systems that let users open several applications at the same time. They are used on devices allowing only one user.

What are multi-user operating systems?

Operating systems allowing users in networks to access the same computer from their terminals. Each user is given processor time and problems with one system don’t affect the others.

What are TCP models?

Models determining how different computers should be connected to the internet and how they transmit data.

What are OSI models?

Models that help diverse communication systems communicate with standard protocols.

How do operating systems manage networking?

• Showing users available networks

• Using airplane modes to turn off all network connections

• Resending packets of data that have not been received correctly

How do operating systems manage memory?

They allocate programs an amount of RAM to store instructions and data. The CPU then reads these instructions and data.

How do operating systems manage security?

They have user permissions to prevent people who are not administrators from accidentally damaging important files.

How do operating systems manage multi-tasking?

• Storing running programs in the RAM with set amounts of time to use the CPU.

• When the next program runs, values on the CPU are moved to the RAM and the program can be run again.

• By switching quickly, multiple programs can be run at the same time.

How do operating systems manage device drivers?

Device drivers send signals to hardware which are translated so that software can understand them. When signals are received, they are put into queues until operating systems are ready to process them.

What is proprietary software?

Software which is legally owned and manufactured by a person or company.

What is open-source software?

Software that is available for anyone to use and modify.

What are the advantages of open-source software?

It is often free and easy to customise.

What are the advantages of proprietary software?

It is more advanced than open-source software, has higher security measures and is better integrated with company systems.