• switches can send and receive data simultaneously - they are full duplex
• a hub is half duplex- only one host can communicate at a time.
• a hub broadcast signals to all computers connected in a network while a switch directs data to its intended destination

– knowledge base
– rule(s) base
– inference engine
– explanation system
– (expert system) shell

Benefits

• The user is not restricted to the predetermined options//the GUI uses icons and set menus
• The user has more control over the computer settings//in GUI computer settings are protected from the user
• Uses less memory than GUI
• Requires less processing power for the interface
• More processing power is made available for the task

Drawbacks

• The commands used have to be learnt
• The commands used have to be remembered
• The commands used have to be typed in/entered exactly
• Have to remember the exact path/correct name of application
• More prone to errors on data entry Commands have to be typed in//in a GUI can use touchscreens/mice
• Tends to be used by specialist people//GUI is more user-friendly and can be used by non-experts

• mirrored hard disk/hot standby/second computer
• re-run the old master file with the transaction file

•  map IP addresses to names and criteria
• To map directory services
• Maintain directory of domain names
• To map URL (web address) to IP address

2.1.1 Explain the concept of open source in the context of FOSS. (2)

• Is a software whose source available and user can modify and redistribute

Give ONE example of a free operating system the company could install on a laptop. (1)

• Linux
• FreeBSD
• ReactOS
• Android
• ChromeOS
• OpenSolaris

2.1.3 State TWO disadvantages of using free open-source software.

• Lack of support
• Security risks
• Compatibility issues
• Hidden costs

An action query is used to modify, add, or delete data in a database whereas a select query is used to retrieve data from a database based on specified criteria but does not make any changes to the data.

• Firmware is a software program permanently etched into a hardware device such as a keyboards, hard drive, BIOS, or video cards.
• Device drivers are operating system-specific and hardware-dependent. A device driver acts as a translator between the hardware device and the programs or operating systems that use it. 
• Firmware is a software that controls a system, and firmware's functionality ranges from performing basic tasks like minimal I/O controls to full-fledged software system running with simple or no OS, with scheduler, memory management, etc. 
• A driver, on the other hand, is usually part of the operating system that performs the specific task of controlling a hardware component like a display or USB controller, etc., and gives an interface to use the hardware by Operating system and applications.

• It has electrical components.
• It is programmable.

• They are small and fit in a small storage space
• They are portable hence can be carried when need to be used outside the office
• Low power consumption
• Have rechargeable batteries

• data must be accurate/up-to-date
• personal data must be registered
• data must be used for the purpose that is registered for
• if data is to be used for another purpose the registrar must be notified/
• subject gives consent
• patients must be able to see the data and have it changed if it is incorrect
• processed fairly and lawfully
• kept no longer than needed
• kept secure
• not transferred to other countries without protection

• Resizing using resize handles
• Rotating
• Cropping
• Flipping
• Moving

• By setting the validation rule for the input controls on the property sheet in design view
• By use of VBA to restrict user inputs for a given control on a form
• By use of queries to restrict options available for the user in a combo box or listbox
• Setting correct data types for the fields in table the design
• Enforcing referential integrity in database relationships
• Use of input mask for the controls on the property sheeet in design view

• A compiler translates the whole program in one go whereas An interpreter translates each line of code (often an intermediate code) at run time
• A compiler produces an executable file that will run on the target hardware machine without the compiler being installed  A run time interpreter will be required at run time
• Compilers tend to be large complex programs Interpreters are smaller simpler programs
• Interpreted programs can be amended and run without translating whole program Compiled programs have to be re-compiled after a change
• Compilers compile programs that will usually only run on the target platform (hardware/operating system)  Interpreters will interpret same program (or intermediate code) on different (some virtual) platforms

(a)

• Hardware required by each computer to connect to a network is a Network Interface Card / NIC / network adapter

(b)

• Computer A adds computer D’s address to packet
• Computer A sends packet to switch
• Switch looks at address on packet  Switch compares to stored list of addresses on network
• Switch forwards packet to computer D’s address

device: beeper/loud speaker
use: to indicate barcode correctly read/error in reading barcode
device: (LCD) screen/monitor
use: to show prices and other information about goods
device: touch screen
use: to show prices and other information about goods/to select items that need to be
weighed/identified
device: weighing machine
use: to find weight of loose items (e.g. fruit) to enable pricing
device: (magnetic) card reader/CHIP and PIN reader
use: to read customer’s debit/credit card/enable customer to pay for goods using a
credit or debit card
device: printer
use: to print receipts

Bridge: Joins together two networks that use the same base protocols.

Hub: Copies all packets of data to all devices on the network.

Router: Stores the addresses of computers on the network and transfers data between devices.

Switch : Analyses each data packet and sends it to the computer it was intended for.

• Continually monitoring, evaluating and updating the system once it is operational. Activities include rectifying bugs, requesting changes, updating aspects, finding errors, maintaining code etc.

• virtual memory

• Refers to the delivery of multimedia content, such video or audio over the internet in real-time. It allows users to access and consume content without downloading it to their device beforehand.