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TOPIC 1

System fundamentals

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1.1.1 Identify the context for which a new system is planned.

What is the problem that the new system is going to solve?
Alternative solutions
Staffing: numbers, training
Cost
Time
Compatibility with existing systems
Infrastructure requirements, eg existing network
Bespoke (custom-made) software versus off-the-shelf

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Software: Bespoke vs Off-the-shelf

Made just for you so tailored to your specific needs ✓
Very expensive ✗
May require special training ✗

Off-the-shelf

Made for a general audience so won't have everything you need ✗
Cheap ✓
Skilled workers readily available ✓

Bespoke

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1.1.2 Describe the need for change management.

Communication of the need for and benefits of change
Users may require training
Recruitment may be necessary to bring in suitable skillsets
Stakeholder support
Planning, milestones, completion date
Dependencies between project stages/components
Compatibility between old system and new system
Testing

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1.1.3 Outline compatibility issues resulting from situations including legacy systems or business mergers.

Legacy system: an old technology or computer system, often one that is inherited by one company when another company is bought out
When two businesses merge, their computer systems may be incompatible with each other eg in terms of

Operating systems
Data formats
Hardware

Legacy systems are not always immediately replaced for a number of possible reasons:

They might still work well
It might be too costly to develop a new system
Perhaps users are comfortable and retraining would be too much of an upheaval
Perhaps nobody understands how it works!

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1.1.4 Compare the implementation of systems using a client’s hardware with hosting systems remotely.

This point is about whether you should buy hardware for your system and manage it yourself (in-house), or rent the hardware and have someone else host and manage it (outsourced)

	In-house		Outsourced
✗	High initial cost (have to buy hardware)	✓	Low initial cost (hosting company owns hardware)
✗	Technical skill required meaning recruitment costs and possibly high salary costs	✓	No technical skill required (hosting company has its own skilled staff)
✓	Low ongoing cost (no rental or management fee)	✗	High ongoing cost (rental of hardware or management services)
✓	Full control	✗	Loss of full control
✓	All data kept within the organisation	✗	Potentially security/confidentiality risk

Software-as-a-service is the idea that your software needs are provided by a remotely hosted system, that is managed by an ASP (Application Service Provider), rather than having your own hardware and technical staff. Most organisations have some mix of in-house and outsourced systems.

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SaaS: Software as a Service

Features

Remote hosting of data

A database is hosted and managed on the service provider's site, which may be in a different country from the customer.

Remote processing

Applications actually run on the computers at the service provider's site, rather than on the customer's computers.

Local UI

The user interface on the customer's machine sends input across the network/internet to the running process on the service provider's servers.

Thin client

The customer's computers don't do any processing or store any data; they just send input to and receive output from the service provider's servers.

Advantages

Don't have to purchase expensive equipment; so cheaper due to low set-up costs.

Don't have to recruit technical employees to run the system; cheaper due to lower salary bill.

Disadvantages

Ongoing subscription costs

Data is stored and managed remotely; there is a security risk since the data can be accessed by people outside the company.

Data has to be sent across the network/internet; there is a security risk since the data could be intercepted in transit.

The company may feel it has lost control over its data; for instance, it may want to take back-ups more often but be unable to.

The customer becomes dependent on the service provider; this is risky because if the service provider goes out of business then the customer will need to move all their data to a new provider, which could be costly.

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1.1.5 Evaluate alternative installation processes.

Parallel running Old system and new system at the same time. Very low risk because even if new system doesn’t work the old system is still there to cope with problems. May need extra employees to work both systems at the same time. More work and higher salary costs.	Pilot running New system used by a some limited group, perhaps one office, rather than the whole company. Again low risk because old system is still running. Cheaper than parallel running in terms of extra staff and extra work required. Risk that new system problems won't be detected because number of users and amount of data is unrepresentative.
Phased conversion Going from old system to new system in steps. Longer period of time in which employees can learn to use the new system. Low risk of large problems because each phase implies only a small change. Not always possible. Some systems are all or nothing and cannot be introduced in stages.	Direct changeover "Big bang" or "flicking the switch". Going from old system to new system overnight. Lowest cost if all goes well. Substantial risk from problems with the new system because old system is no longer there to rely on.

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1.1.6 Discuss problems that may arise as a part of data migration.

Data migration is the process of moving data from one system to another, usually an older system to a newer one.
Issues that can arise (according to the guide) are:

Incompatible file formats, data structures, validation rules
Incomplete data transfer
International conventions on dates, currencies and character sets

Data often has to undergo a conversion process before it can be loaded into the new system.

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1.1.7 Suggest various types �of testing.

These are not mutually exclusive alternatives. There is some crossover between them:

Debugging: Ongoing. Happens during development
Alpha testing: The first stage of testing, done by the programmers themselves
Beta testing: Later testing, done by future users when the system is almost finalised
White-box testing: Testing the system from the point of view of the programmer, with full knowledge of how it does what it does
Black-box testing: Testing what the system is supposed to do, from the point of view of the user, with no knowledge of how the program does what it does
Unit testing: Testing the modules or components of the system separately
System testing: Testing the system as a whole
Acceptance testing: The last testing phase once the system is delivered to the user and just before sign-off
Automated testing: Using software to test software

How important is testing? Implementation of a buggy system can lead to loss of productivity, customer dissatisfaction and can mean that users don't want to use the system. This last problem can be very difficult to undo.

Consider how important testing is for each of the implementation strategies in 1.1.5.

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Adv and Disadv of Testing Types

The problem with white-box testing is that because the testers know how the program works, they might subconsciously only give it input that they know will be valid. Since real users do black-box testing, their input is considered more genuine and realistic.

On the other hand, white-box testers will be able to design their tests to cover all of the possible functions of the software, because they know how it works. Black-box testers may only test a small range of the software's function because they don't know what it can do.

The advantage with unit testing is that testers can make sure that every component is tested and nothing is overlooked. With system testing, it's less easy to make sure all components are tested.

On the other hand, unit testing doesn't test whether all components work together, even they work well separately. System testing is needed to make sure that there are no compatibility problems between components.

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1.1.8 Describe the importance of user documentation.

Non-technical (as opposed to system documentation, which is aimed at IT professionals)
Contains friendly advice about installation, operation, troubleshooting
Graphical information like sample data and screens
One of the biggest difficulties with a new system is a userbase that is unwilling or unable to adopt the new system (old habits die hard)
Good user documentation can go a long way to making a new system successful by easing the transition

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1.1.9 Evaluate different methods of providing user documentation.

Paper manuals:

Don't need to be near a computer
Need multiple copies

Online manuals:

Can make use of rich media
Can search
Always available

Interactive tutorials:

Makes the learning process more interesting

Dedicated support teams:

Can give accurate, focused assistance
Increases salary bill

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1.1.10 Evaluate different methods of delivering user training.

Self-study from printed material may be slow, boring, inauthentic and requires users to be highly motivated.
Learning in groups and classes can help users to feel more secure and involved, but it takes time out of the working day and users might be unwilling to attend classes in their free time.
Online/remote training or assistance can reduce travel costs but there can be problems with time zones
Interactive programs make learning fun and don't need to be managed by a person. However, they may provide less focused training and be unable to respond to a particular user's needs.
Practice with the system itself is the most authentic learning experience but it could cause problems with live data.
Allowing users to give feedback gives them a sense of ownership.
Forums and FAQs allow the users to build their own knowledgebase.
A variety of training methods gives users a spectrum of learning experiences.
Dedicated support teams can give focused attention and provide a personal touch.

Company must provide time for training and have a training plan
Basic computer skills – what does the system assume you already know?
Different training for different roles, eg administrator, superuser, end-user
Online interactive training programs
A support department
"Hands-on" – practise with the system itself
Group activities and role play
Blogs, wikis, forums, FAQs
Getting feedback from users

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1.1.11 Identify a range of causes of data loss.

Viruses, malware, deliberate deletion of data
Natural disasters, such as fire, earthquake, flooding.
Hardware failure
User error (accidental deletion)
Physical damage, eg dropping a hard disk
Power failure can cause data that has not already been written to disk to be lost. It can be mitigated by using a UPS (uninterruptible power supply)
Back-ups are essential but they present extra security issues.

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1.1.12 Outline the consequences of data loss in a specified situation.

Business activities may have to be suspended

You can't deliver goods to your customers if you have lost all their orders
You can't bill your customers if you have lost their account details�

It is damaging to an organisation's reputation

Customers may have to be notified�

There may be costs associated with replacing the data

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1.1.13 Describe a range of methods that can be used to prevent data loss.

Back-up

Removable media: Cheap, simple to install (USB), large capacity, easy to move offsite. Also easy to lose!
Offsite: Take back-ups offsite in case of disasters like fire or flooding.
Online: Always available, need internet connection, possible security risk.

Antivirus: Prevent malware from deleting/editing data.
Failover and redundancy:

A redundant system is a clone of an existing that is kept up-to-date in case the primary system fails.
Failover is the process of detecting a failure of the primary system and switching users to the redundant system.
This is often done with large enterprise servers because of the high cost that would be associated with a server outage.

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1.1.14 Describe strategies for managing releases and updates.

The software life cycle involves continuous monitoring, testing, bug-fixing and re-development
Hence the need for multiple releases and updates of software
Reasons include:

Bug-fix (often called a "patch")
Security threat
User requests
Additional features

Mechanism: Software compares current release with latest release via internet. If the current release is out-of-date, the newer version is downloaded and installed.
Some software allows automatic update option, eg Windows update.
Possible issue: How do you know that the update is genuine? How do you know that it doesn't grant the software extra privileges that you wouldn't have agreed to on first installation, eg accessing your contacts?
Possible solution: On first install, Android apps have to declare the privileges they require, and they can update themselves only if they do not require extra privileges.

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1.2.1 Define the terms: hardware, software, peripheral, network, human resources.

Hardware: The machines, wiring, and other physical components of a computer or other electronic system
Software: The instructions and data that can be stored electronically in a computer system.
Peripheral: A computer device, such as a CD-ROM drive or a printer, that is not part of the main computer but which is added to provide some extra function.
Network: A group of two or more computers linked via a wired or wireless communication medium.
Human resources: The personnel or workers of a business or organization, esp. when regarded as a significant asset.

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1.2.2 Describe the roles that a computer can take in a networked world.

Client: A computer on a network that makes requests to a server. Example: Your computer on the school network. When you go to student resources and double-click a file you are making a reques of the school's file server.
Server: A computer on a network that listens to and responds to requests from clients. Examples are file servers, database servers, web servers, etc.
Email server: A computer on a network dedicated to sending and receiving email.
DNS server: DNS = Domain Name Service. A computer on a network that translates between user-friendly names of network resources and their numerical IP address. Example: User-friendly name: www.yahoo.com, IP address: 206.190.36.150.
Router: A computer on a network that is responsible for sending network packets to the right host, subnet or network.
Firewall: A computer on a network that limits the flow of data packets for a number of different reasons including: port number, application, content

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Firewalls

A firewall is a program that restricts data allowed into and out of a network, on the basis of a set of rules
One of the ways it does this is to close certain ports. A port is an identification number for a process running on a machine.
Try playing World of Warcraft using the school’s internet connection. You will fail. Why? Because the WoW software uses certain port numbers but the school’s firewall blocks traffic on those ports.
Other ways you can block traffic is by its source address, destination address, or the application that its coming from.
The word “firewall” can refer to the software itself, or the hardware on which the software runs. Often a firewall is a dedicated machine that does nothing else.
"Next generation" firewalls can actually open up and inspect the contents of packets and so can help to detect viruses.

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1.2.3 Discuss the social and ethical issues associated with a networked world

I have generally tried to concentrate all social and ethical stuff into one slide (1.2.11)
Also see discussion in Topic 3

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1.2.4 Identify the relevant stakeholders when planning a new system

A "stakeholder" is any person or organization that is actively involved in a project, or whose interests may be affected positively or negatively by execution of a project.

Examples are:

End-users of the planned system

Basic user, superuser, administrator

Other employees
Customers
Suppliers
Shareholders
Unions
Local community
Etc

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1.2.5 Describe methods of obtaining requirements from stakeholders.

Surveys:

Adv: You can get information from a lot of people quickly
Disadv: The survey may not ask the right questions. Qualitative information difficult to quantify.

Interviews:

Adv: Stakeholders can make you aware of things you hadn't thought of, unlike with survey in which their answers are restricted
Disadv: Time-consuming. Stakeholders may give biased information.

Direct observations:

Adv: Avoids bias.
Disadv: Time-consuming. Observer can affect the process.

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1.2.6 Describe appropriate techniques for gathering the information needed to arrive at a workable solution.

Examine the current system to see how it works. What are the inputs and outputs? What processing is done? What different roles are there for the users?
Competing products can give ideas about different way to achieve the same aim.
Organisational capabilities. Are there experts within the organisation who can be consulted?
A literature search is the term given to a systematic study to previous project reports to in an attempt to see if the problem has already been solved by someone else

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1.2.7 Construct suitable representations to illustrate system requirements.

Structure diagram

This just shows how something can be broken down. It doesn't imply any sort of sequence.
You probably all did or will do one as part of your IA
I would be surprised to see this on the exam outside of an inheritance hierarchy diagram

Main problem

Small �task A

Small �task B

Small �task C

Note: If you do Option D, don't confuse this with an inheritance hierarchy! Just because one box appears above some others, doesn't imply inheritance. This, in fact, is a composition hierarchy.

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1.2.7 Construct suitable representations to illustrate system requirements.

Data Flow Diagram

The guide does mention DFDs but I don't think it has been thought through properly
DFDs are very specific things and constructing them takes a long time
I can't believe there is any way you will be asked to create one in an exam

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1.2.7 Construct suitable representations to illustrate system requirements.

Systems Flowchart

I have seen this regularly on the exam
Exact use of the right symbol is not important
You need to think about inputs, processing, outputs
They are often X-shaped with inputs at the top of the X, processing as the middle, and outputs at the bottom

Tape Storage

Disk Storage

Document

Process

Input/ Output

Manual Input

Documents

Master File

Payslips

Calculate Pay

Hours worked

Updated Master File

Transaction File

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1.2.7 Construct suitable representations to illustrate system requirements.

Systems Flowchart Examples

Customer orders are collected on paper, keyed in, and stored in the customer orders file. A stock master file is searched to determine whether sufficient stock is available and an appropriate report is produced. Construct a systems flowchart representing the process described above. [5 marks]

A program accesses a text file on disk. To edit the text the user of the program enters data using a keyboard. The program then amends the text which was read from the file, writes the updated file back to disk and produces a printed report of all amendments made to the text file. Construct a systems flowchart representing the process. [4 marks]

A sequential transaction file is sorted, stored onto a hard disk,

and a printed report is produced. Construct a systems flowchart representing the process. [4 marks]

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1.2.8 Describe the purpose of prototypes to demonstrate the proposed system to the client.

Allows the user to give the developer immediate feedback
Gives the client a better sense of what the software will be like because it's easier to understand a prototype than, say, a written description
Allows the developer to verify that he understands the requirements
Allows the client to change/amend requirements before the software is developed
This reduces costs in the long term
And saves time

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1.2.9 Discuss the importance of iteration during the design process.

Once the system is in use, users might find:

bugs
unfulfilled requirements
new requirements
improvements

There may be changes to other systems that necessitate changes, eg a new operating system
Any changes to a system start a new cycle of design and development

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1.2.10 Explain the possible consequences of failing to involve the end-user in the design process.

The end-users are the experts and they know what they need from the system better than anyone
If users are not involved in the design process, there is an increased chance that the software will be designed inappropriately
If this happens, the client will end up not using the software
This means that the development cost will have been wasted
There may also be reduced productivity in the client organisation
Involving the user requires constant communication in a variety of ways, including surveys, interviews, focus groups, responses to prototypes, etc

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1.2.11 Discuss the social and ethical issues associated with the introduction of new IT systems.

Summary of Social and Ethical Issues

privacy of the individual – security of data and information
accuracy of data and information
changing nature of work
appropriate information use
health and safety
copyright laws

Social and ethical issues in collecting

bias in the choice of what and where to collect data
accuracy of the collected data
copyright and acknowledgment of source data when collecting
the rights to privacy of individuals on whom data is collected
ergonomic issues for participants entering large volumes of data into an information system

Social and ethical issues associated with organising

current trends in organising data, such as:
the increase in hypermedia as a result of the world wide web
the ability of software to access different types of data
a greater variety of ways to organise resulting from advances in display technology
the cost of poorly organised data, such as redundant data in a database used for mail-outs
the appropriateness of a two digit date field at a time when storage and processing was more expensive, versus the current inappropriateness

Social and ethical issues associated with analysis

unauthorised analysis of data
data incorrectly analysed
erosion of privacy from linking databases for analysis

Social and ethical issues associated with storing/retrieving

the security of stored data
unauthorised retrieval of data
advances in storage and retrieval technologies and new uses such as data matching

Social and ethical issues associated with processing

types of computers on networks
flexibility from the distributed processing of personal computers on networks
security from the centralised processing of network computers (terminals)
ownership of processed data
bias in the way participants in the system process data

Social and ethical issues associated with transmitting and receiving

accuracy of data received from the Internet
security of data being transferred
net-etiquette
acknowledgment of data source
global network issues, time zones, date fields, exchange rates
changing nature of work for participants, such as work from home and telecommuting
current developments and future trends in digital communications, radio and television
the impact of the Internet on traditional business

Social and ethical issues associated with displaying

communication skills of those presenting displays
past, present and emerging trends in displays
appropriate displays for a wide range of audiences, including:
standards for display for the visually impaired
displays suitable for young children

Social and ethical issues associated with Planning, Design and Implementation

machine-centred systems simplify what computers do at the expense of participants
human-centred systems as those that make participants’ work as effective and satisfying as possible
how the relationships between participants change as a result of the new system
ensuring the new system provides participants with a safe work environment
awareness of the impact the system may have on the participants:

opportunities to use their skills
meaningful work
need for change
opportunities for involvement and commitment

Social and ethical issues related to information systems and databases

acknowledgment of data sources
the freedom of information act
privacy principles
accuracy of data and the reliability of data sources
access to data, ownership and control of data
new trends in the organisation, processing, storage and retrieval of data such as data �warehousing and data-mining

Social and ethical issues related to communication systems

the use of communication systems to share knowledge, not just data
issues related to messaging systems

ideas delivered by this means appear less forceful and caring than ideas delivered personally
danger of being misinterpreted
power relationships
privacy and confidentiality
electronic junk mail
information overload

implications of Internet trading including:

local taxation laws
employment ramifications
nature of business

trading over the Internet and its commercial implications
the difficulties of censoring content on the Internet
issues arising from Internet banking, including:

security of banking details
changing nature of work
branch closure and job loss

the removal of physical boundaries by enabling:

work from home
virtual organisations, ie organisations structured around the communication system
removal of national and international barriers to trade

how participants are supported:

individuals by providing a means for communication
participant teams by enabling the exchange of ideas and data

the emerging trend of accessing media such as radio and video across the Internet

Social and ethical issues related to multimedia systems

copyright: the acknowledgment of source data and the ease with which digital data can be modified
appropriate use of the Internet and the wide spread application of new developments on it such as live video data
the merging of radio, television, communications and the Internet with the increase and improvements in digitisation
the integrity of the original source data in educational and other multimedia systems

Social and ethical issues related to transaction processing systems

changing nature of work and the effect on participants, including:

the automation of jobs once performed by clerks
the bypassing of clerks by people in the environment performing their former roles�(Eg collecting now done by customers using the bank's ATM machines instead of via the bank clerk)

the need for non-computer procedures to deal with transactions when the computer is not available in real time systems
bias in data collection:

when establishing the system and deciding what data to collect
when collecting data

the importance of data in transaction processing, including:

data security
data accuracy
data integrity

control in transaction processing and the implications it has for participants in the system

There is a good chance you will have to talk about issues like these in your exam, possibly in the context of a given scenario, for up to 6 marks. Familiarise yourself with this slide. I suggest you zoom in.

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Social and environmental implications of computing

I strongly recommend the use of Atkisson's Sustainability Compass in tandem with the Sustainable Development Goals when considering these issues.

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1.2.12 Define the term usability.

Usability: The notion of how easy a system is to learn and use

Learnability: How easy is it for users to accomplish basic tasks the first time they encounter the design?
Efficiency: Once users have learned the design, how quickly can they perform tasks?
Memorability: When users return to the design after a period of not using it, how easily can they reestablish proficiency?
Errors: How many errors do users make, how severe are these errors, and how easily can they recover from the errors?
Satisfaction: How pleasant is it to use the design?

Ergonomics: designing and arranging things people use so that the people and things interact most efficiently and safely
Accessibility: The ability of people to access and benefit from some system. Often people with disabilities or special needs.

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1.2.13 Identify a range of usability problems with commonly used digital devices.

Students should be aware of usability issues in a range of devices including PCs, digital cameras, cell phones, games consoles, MP3 players and other commonly used digital devices. [IB guide]

Confusing navigation
Lack of help
No search facility
Small, fiddly buttons
Too complex, too many functions

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1.2.14 Identify methods that can be used to improve the accessibility of systems.

Touch screen
Voice recognition
Text-to-speech
Braille keyboard
Screen magnifier
Font adjustment and zoom

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1.2.15 Identify a range of usability problems that can occur in a system.

These should be related to the following systems:

Ticketing: I have no idea what this means. Ticketing usually applies to help desks, ie support tickets. I guess time zones could be a problem when you need online support.
Online payroll: Internet downtime, currency dependent
Scheduling: Time zone wrong
Voice recognition: Can't understand accents/languages or speech-impaired users
Systems that provide feedback: Feedback not provided in a usable format. Compatibility.

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1.2.16 Discuss the moral, ethical, social, economic and environmental implications of the interaction between humans and machines.

Toxic e-waste
Increased power consumption and use of fossil fuels
Pollution��Automation (robots) of human jobs, leading to unemployment
Overdependence on internet / computer systems

Increase in quality of life? Efficiency gains.
Overcoming medical disabilities with implants and intelligent prosthetics
Computers can work in dangerous environments, overnight, etc.
Use in warfare :(��

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