TOPIC 1System fundamentals (20 hours)

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

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

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!

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.

1.1.5 Evaluate alternative installation processes.

Parallel runningOld 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 runningNew 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 conversionGoing 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.

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.

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• 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• White-box testing: Testing the system from the point of view of the

programmer, with full knowledge of how it 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• 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.

1.1.8 Describe the importance of user documentation.

• Non-technical (as opposed to sytem documentation)• Installation, operation, troubleshooting• 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

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

1.1.10 Evaluate different methods of delivering user training.

• 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

• 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.

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.

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

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.• 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

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.

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.

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

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

• Zzzzz• See notes to 1.2.11• See discussion in Topic 3

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

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.

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

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 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

1.2.7 Construct suitable representations to illustrate system requirements.

Data Flow Diagram• 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

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

DocumentProcess

Input/ Output

Manual Input

Documents

Master FileTransaction

File

Payslips

Calculate Pay

Hours worked

Updated Master

File

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]

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

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

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

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-miningSocial 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 InternetSocial 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 systemsSocial 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

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.

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

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

• https://www.apple.com/accessibility/ios/• http://www.microsoft.com/enable/products/windows8/• http://www.google.com/accessibility/products/

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.

1.2.16 Discuss the moral, ethical, social, economic and environmental implications of the interaction between humans and machines.• Oh God no. Please make it stop. Make the bad man go

away.• See 1.2.11