[Shiva Chandnani]

In general terms what is the meaning of the term resource?
– something that can be used by a person or organization in order to function effectively.

Choose any 3 key resources within a computer system and describe the impact if the resource is limited. If applicable, describe how the operating system plays a role in sharing the given resource.

Processor
– if the processor is limited then the amount of task that the computer can execute is also limited. the stronger the processor the more tasks it is able to complete more tasks in a shorter amount of time. The operating system receives input from the user and provides tasks for the processor to complete. the processor then works with other components in the computer to complete the given task.

RAM
– If ram is limited then the computer is forced to send and store data on virtual memory which is a much slower process as secondary forms of memory is not as fast as ram. Thus this results in the programs running much slower. The operating system communicates with the CPU, which then the CPU communicates with the RAM and other components of memory all in order to complete a given task.

Hard Drive
– Hards drives are a non-volatile form of data in which if it is limited or up to its max capacity, the user may be unable to store anymore programs and files onto the computer. This limits the usability since any task that require data to be stored in the hard disk would be unable to execute. All files and programs are usually stored on the hard-disk including the operating system as well. The hard drive also communicates with the operating system through the CPU. The CPU sends data to the hard disk using it as a tools to complete tasks.

[Shiva Chandnani]

1. Audio files and images
2. When using lossy and lossless compression to download files, it will result in taking less time to download and taking up less of the users data storage. Lossy compression usually is stored in less data that lossless. Lossy compression results in the size of the file being reduced by eliminating data in the file. Lossless compression is such that it does not lose any data in the compression process. Lossless compression “packs” data into a smaller file size by using a kind of internal shorthand to signify redundant data.
3. If all data on the file is important to the user and they do not want to lose any of that information then a lossless compression is more important.Another factor to use lossless compression would be if the user is not short on data storage space and doesn’t mind the file taking up extra space on their computer.

[Shiva Chandnani]

1 ) Describe with an example how run Run Length Encoding can be used to compress an image.

it reduces repetitiveness in order to save data by compressing data by specifying the number of times a character or pixel color repeats and by the value of the character or pixel. So by storing the color and the amount of colors in a row it can save space on images especially where there is only a few colors on it. For example a picture of a sunset only has a few main colors with the rest of the pixels repeating that color, such as orange or red. so using run length encoding will help store the information in much less bites than usual.

[Shiva Chandnani]

1). File compression is when the size of a file is reduced by re-encoding the file data to use fewer bits of storage than the original. It is necessary to compress files becuase users get to save storage space, have faster transmission time over networks, and many other ways which help saves cost and effort.
2). Lossless compression compresses data but does not remove the quality or main aspects of of the data, however lossy compression does permanently remove data which may lead to a reduction in quality of a photo for example. for example when transferring a mp3 file over a network there may be parts that there is no sound or is repeated, so using lossy compression can reduce the data file and still maintain the quality of the file.
3) GIF and JPEG are lossy while PNG, BMP and Raw are lossless formats for photos. for Audio files, OGG, MP4 and MP3 are lossy formats, while ALAC, FLAC and WAV are all lossless formats.

[Shiva Chandnani]

INTLIST = [4,3,5,6,1,9,0,9,7,4,7,8,9,0]
NEXTLIST = = [4,3,5,6,1,9,0,9,7,4,7,8,9,0]
FREQLIST = 0

loop for i from 0 to n-1
loop for j from o to n-1
if INLIST[i] = NEXTLIST[j] then
FREQLIST = FREQLIST + 1
end if
end loop
end loop
output FREQLIST

[Shiva Chandnani]

TENNIS = [“Al”,”Bobby”,”Carla”,”Dave”,”Ellen”]
BBALL = [“Lou”,”Dave”,”Hellen”,”Alan”,”Al”]

loop for i from 0 to n-1
loop for j from 0 to n-1
if tennis[I] = Bball[j] then
output tennis[i]
end if
end loop
end loop

[Shiva Chandnani]

1. Create a post That identifies 4 components specific to setting up a VPN can be a mix of hardware and protocols.
– VPN server- to handle and manage incoming VPN traffic and to establish and manage VPN sessions and their access to network resources. This set up by the VPN provider
– Encapsulation – Uses an extra layer over the packets. The outer packet protects the contents from public view and ensures that the packet moves within a virtual tunnel unidentifiable by service providers.
– Asymmetric Encryption keys – Uses public and private keys to encrypt and decrypt data.
– Authentication – VPNs mask your IP address and establish a secure and encrypted connection.

2. Briefly describe how VPN’s can be used and how they have impacted working life and social life.
– VPN’s allow people, such as traveling employees, a secure and reliable way to connect to their business’s computer network from remote locations. This impacts working life as people can now work from home allowing more flexibility. It affects peoples social lives as it provides users with security of their data, so the fear of users being hacked is reduced. VPN’s have created a safer environment for users giving them more confidence that their private data won’t be access by third parties.

[Shiva Chandnani]

Review Systems Design and Fundamentals

Past Paper Questions

1. Human interaction with the computer system includes a range of usability problems.

(a) Define the term usability. [1]
– Usability is a measure of how well a user can use a product/design to achieve a goal effectively and efficiently.

(b) Identify two methods that could be used to improve the accessibility of a computer
system. [2]
– Implement hearing features that allow people with disabilities to use the system without assistance. Implement vision features that allow people with disabilities to use the system without assistance.

4. A small hotel buys a software package to manage their bookings.

(a) Describe two types of documentation that should be provided with the software package. [4]
– A user manual provides the end-user with information on how to use the system and all of it’s features.
– FAQ document Provides frequently asked questions, so if the end-user has the same questions they can potentially find the answer on the document.
(b) State two methods of delivering user training. [2]
– one-to-one classes
– Self instruction
7. A hardware shop supplies a wide variety of bathroom equipment. There are 15 shop
assistants who serve customers, 3 office staff who handle the administration, and a manager.

A specialized company is asked to design and implement a new computer system for
the shop.

(a)
(i) Identify two different types of users of the system. [2]
– The manager and the office staff.
(ii) Explain the role of users in the process of developing the new computer system. [3]
– Users are in frequent communication with the developer in order to design the system according to the likings and needs of the users. The user set the requirements for the system at the beginning and then throughout the process of building the system the developer may stay in contact with the users if further question come up or if a prototype testing is required. Then at the end the end user conducts post-system development testing such as a black box testing.
(b) Describe why it is useful to produce more than one prototype of the new system. [2]
Having multiple prototypes helps I,proves the end-user satisfaction at the end of the process. Having multiple prototypes allows the the end-user see multiple stages of the system and provide feedback and new requirements based on their likings. If only a few prototypes are made then there is a possibility that at the end the end-user may want to change a certain feature, which will be much harder for the developer to conduct.
(c) Outline two problems that may occur when transferring data from the old system to the
new system. [4]
– The first problem is that there may be data loss.when transferring the data from the old system tot the new system data can be lost in the process if a problem accords during the transfer. Next is that there may be compatibility issues when transferring the data. the new system may not be able tot understand or comprehend the data being inputed form the old system.
The new system is implemented using parallel running.

(d)
(i) Outline what is meant by parallel running. [2]
– parallel running is when both systems are running at the same time. The old system and the new system are both running together allowing access to both systems at any given time.
(ii) Outline one reason for choosing parallel running as opposed to a direct
changeover. [2]
– Parallel running greatly prevent data loss when choosing to implement a new system because if the new system fails upon launch the old system will still be running so the data will still be available and accessible on the old system. In a direct changeover, if the new system fails then there won’t be a back up system running resulting potential data loss.

2021 Paper

12 A school has a cabled network and wishes to add wireless networking access for the whole campus.

Describe 2 hardware components the school will need to implement the network
– a wireless router and a network switch. The router will provided access to other networks and the switch will allow nodes within the system to communicate wirelessly.
Identify 2 advantages to the students of the new wireless network
– it promotes mobility as now the students can access the network anywhere in the schools premise prevent their limitation to be connected to a Ethernet cable. another advantage is that it allows a larger network area as the network is no longer limited to the distance the Ethernet cables go.
There are concerns that unauthorized people may gain access to the data on the network

(c) Outline 2 methods that the school could employ to prevent network data being accessed over the wireless network.
– set up a firewall
– unauthorize access to unknown websites and systems.

[Shiva Chandnani]

1D array exercise

Largest = 0
Smallest = ArrayTemp[0]
ArrayTemp = [23.1,10,12,23,14,17,19.2]
loop for i from o to n-1
if ArrayTemp[i] > Largest then
Largest = ArrayTemp[i]
end if
if ArrayTemp[i] < Smallest then
Smallest = ArrayTemp[i]
end if
end loop
output Largest – Smallest

part b).

Loop for i from 0 to n-1
if inventory[i] < 10 then
prices[i] = prices[i]*1.2
end if
end loop

[Shiva Chandnani]

SURNAME = [ ]
FIRSTNAME = [ ]

loop for i from 0 to n-1-i
loop for j from 0 to n-1-i
if SURNAME[j] > SURNAME[j+1] then
larger = SURNAMES[j]
SURNAME[j] = SURNAME[j+1]
SURNAME[j+1] = larger
larger = FIRSTNAME[j]
FIRSTNAME[j] = FIRSTNAME[j+1]
FIRSTNAME[j+1] = larger
end if
end loop
end loop

[Shiva Chandnani]

[Shiva Chandnani]

SURNAME = 0
FIRSTNAME = 0
i = 0
NAMES.resetNext() //restarts to the beginning of the collection
loop while NAMES.hasNext() = True //looping throught he collection using a while loop
SURNAME[i] = NAMES.getNext(). //storing the Surnames into a seperate array
FIRSTNAME[i] = NAMES.getNext(). // Storing the First Names into a other array
i=i+1 //allows us to add the names into the next space in the arrays
end loop

[Shiva Chandnani]

Review Activities

1) Discuss the differences between usability and accessibility.
– Usability refers to the potential the product has to accomplish its users’ goals, such as adding a screenshot feature to a device, etc. However, accessibility is referred to the potential to meet the needs of as many different types of individuals as possible, such as people with disabilities, etc.

2) List 6 examples of assistive technology.
– screen readers
– Braille keyboards
– Voice synthesizers
– speech to text
– closed captions
– screen magnifiers

3) Select an operating system, example Windows 10 and describe the accessibility features for vision and hearing. Link for Windows 10, but you may choose a different operating system https://www.microsoft.com/en-us/accessibility/
– on the operating system of IOS, the accessibility features for vision include Voiceover, Zoom, Audio descriptions, and Display and text size. for hearing-related accessibility features, they provide paring with hearing devices, Sound Recognition, Text to speech, and Subtitles & Captioning.

4) What is neurodiversity?
– it is the idea that people experience, interact with, and interpret the world in unique ways. It is a viewpoint that brain differences are normal, rather than deficits

5) Briefly describe some ways that the operating system selected in 3 above caters for neurodiversity.
– Apple IOS offers text suggestions, customizable accessibility shortcuts, and touch assists.

6) Choose a device and identify a range of usability problems that can occur in that system. Device can be PCs, digital cameras,
cell phones, games consoles, MP3 players or other commonly used digital device

Cell Phones
– short battery life
– too small words and icons that may be unreadable to the user
– speakers may not be loud enough to understand

7) Select a system from ticketing, online payroll, scheduling, voice recognition. For selected systems identify a range of usability problems
that can occur in your system.

Voice recognition (range of usability problems)
– limited dictionary in the voice recognition software
– the system won’t be able to understand people with a speech impediment
– the system may not be able to understand certain dialects/accents of a language.
– If the user is in an area will a lot of abient noise then the system may not be able to understand what the user is saying.

8)For the moral, ethical, social, economic, and environmental implications of the interaction between humans and machines. For each one briefly discuss the pros and cons
– Moral: We are able to communicate to more people through machines allowing us to learn more morals. A disadvantage to it is that there are chances of piracy taken by humans through machines.
– Ethical: people can share their opinions easier promoting free speech. However, there can be many cases of invasion of privacy since it is possible for third-party individuals to access private information illegally.
– Social: Increased Global Interaction and communication, However people are speaking to each other less face to face. People use technology as a distraction to socializing with people.
– Economic: The interaction has provided more jobs such as web designers. A disadvantage is that machines are also take away jobs from people such as cashiers and factory workers.
– Environmental: living a more digital life allows people to reduce the amount of fossils fuels burnt, for example, online shopping, working from home, teleconferencing limits a person’s travel and their fossils fuel consumption. A disadvantage is a fact that if more machines are used more energy is required to run them, thus more fossil fuels are burnt to leave the environment worst off.

[Shiva Chandnani]

What is data redundancy and how can it be used to prevent data loss.
– It is when the same piece of data is held in two separate places in a data storage technology or whenever data is repeated. it can be used to prevent data loss so that when the primary system fails the backup system continues to run and still has all the necessary data, also called a failover system.

Activity A, list a range of causes that can result in data loss. Choose 4 and explain by giving an example. Example user error. User hits exit without saving and suggests how that might have been prevented
– Power Outages – There is a thunderstorm that results in the electrical grid short-circuiting results in a city-wide power outage. this can be prevented by having your home or business have a backup generator or save your data frequently as you work to limit the data lost.
– Computer Theft – While at the park user leaves his laptop unattended to use the bathroom and when he returns his laptop is stolen. This is preventable by carrying your computer with you at all times when in a public place.
– Liquid Damage – User spills coffee on his computer’s CPU resulting in internal damage. This is preventable by not keeping liquids next to computers or have a liquid container with a lid.
– Viruses & Malware – User downloads a fake software update through his email and his computer ends up getting a virus. This is preventable by being aware of different methods of receiving viruses or by installing anti-virus software onto your computer’s system.
– Hackers and Insiders
– Software Corruption
– Hard disk Crash

Activity B Using an example other than school records outline the consequences of data loss.
– If a hotel loses its online data, it has lost all customer room bookings, records of which rooms each customer is staying at, records of the payment required by each customer. The hotel would have to redo all bookings, bother their customers with the allocation of hotel rooms and further information which only results in customer dissatisfaction resulting in a bad reputation for the hotel.

Activity C You have been tasked with implementing a set of procedures to limit the risk of data loss. Details these with an explanation of why they are necessary ( use the same scenario) as in Activity B
– Having a backup system so that if the primary system fails the backup system or failover system will take over resulting in no data loss.
– Storing backup data/system on a cloud server.

Components of a computer system
Past Paper Question

A small company has a LAN connecting its various desktop computers and peripheral devices.
The company is going to provide Internet access to its LAN.

(a) State the name of an additional hardware device that would be required to permit
Internet access. [1 mark]
– Router

(b) Explain how a firewall would help to provide security for the LAN. [3 marks]
– A firewall would prevent unauthorized access into the LAN system. It would monitor packages sent into the system and would protect it from unauthorized data. The firewall sets a certain group of rules that the computers have to follow in order to maintain security within the system.

(c) Suggest, with reasons, two further measures that the company should take to
safeguard its data from unlawful access via the Internet. [4 marks]
– Only allow the computers to be used for work purposes by the employees. This limits the users/employees accessing certain websites that are not trustable under the the companies LAN for their personal reasons.
– Restrict online downloads from websites that are not trusted. This limits the risk of potential breach into the LAN as websites considered not trusted by the system or firewall won’t permit downloads onto the computers.

Q What hardware component is needed to extend a LAN to a WAN?
– A router

Q Outline 3 key differences between a Switch and a Router.
– 1. A switch transfers data from one node in the network to another, while a router transfers data between two separate systems.
– 2. A router permits the system access to the internet. while a switch only allows access with the specific LAN
– 3. A switch works on the data link layer of the OSI model while a Router works on the network layer of the OSI model.

Q What is the key difference between a HUB and a Switch?
– The switch finds the destination address of the received IP packet and forwards it to the destination address, sending the required data to a specific location. While a HUB will send the packet to all devices in the system.

Q We looked at hardware components to set up a LAN what are the hardware components need to set up WLAN.
– A wireless router is the main component.

[Shiva Chandnani]

What is the difference between local computing and cloud or remote computing?
– Local computing is when your processes of running your software etc. are done locally/in-house. Cloud computing is when your running processes like software are accessed through the internet and is remote.

Why is remote hosting called cloud computing?
– this is because when systems are hosted remotely they are accessed to users through a cloud or the internet.

Give some examples of cloud applications/software?
– Facebook, YouTube, Netflix, Instagram, Google Docs, Gmail, etc.

Software Updates

What is the difference between a patch and a software release?
– A software patch is an update used to fix problems and bugs in the system. A software release is generally when a new functionality of the software is released.

What is the difference between manual and automatic updates?
– Manual updates the user has to access the update and allow the update to occur, whereas for automatic updates the update is done without asking the user and is done by the system itself.

What is end-of-life software?
– it is software that will no longer be receiving updates and/or promoted by the developer anymore.

Create a company policy for Software Updates ( what you should and should not do )
– only download software updates through the developer’s website.
– Do not update through emails sent to users.
– back-up data before updating

End-User Training

Choose 2 methods of delivering software training and compare and contrast the advantages and disadvantages.
– Self-instruction:
Advantages: The quickest form of training and done personally. Also, this method can also be very cost-effective compared to the other methods.
Disadvantages: Requires users to be experienced computer users as they are more confident to start using an unfamiliar system alone to figure out how it works.

– Personal training
Advantages: Training can be suited to user’s needs and abilities since there is a single instructor for the individual user.
Disadvantages: Time form of training is usually the most expensive type of training.

Data Loss

Best Practice

The Power school application at Wells is hosted in-house. A weekly backup is taken, which is stored in the cloud.

What are the dangers of this policy? Formulate a new fail-safe backup policy, money is no obstacle.
– if there is a breach/hack or damage done to the system before the weekly backup is taken, all data from that week can be lost. An alternate system to ensure that data loss is taken to the minimum is to create a more frequent backup, which can be done every minute or every hour.
Will your new policy make data 100% safe?
– Data is never 100% safe and is always susceptible to data loss.

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