1. Analysis and Design Phases
Taken from the “Software Development” textbook
Chapter 3
M. Sanchez

2. How much do you know? Information Systems?
Types of Information Systems? Their purpose?
Goals?
Objectives?
Mission statement?

3. The purpose of information systems
Serves organisations
Aims and objectives directly related to the IS
A mission statement describes the organisation’s reason for existence, its focus and direction
Organisations are groups of people working together towards a common goal
The operational objectives determine the size and type of IS
Operational goals concerned with the efficiency and effectiveness of the operations of the organisation

4. Have you learned?
Analysis and Design worksheet Question 1-5

5. The purpose of information systems
An information system can aid in the achievement of an efficient operation of an organisation
An IS can reduce:
the cost of processes in the production of services and goods
Amount of effort taken by staff
Time taken to complete essential activities
An IS can aid in the achievement of an effective operation of an organisation (better quality products and services)

6. Problems in organisations
Two types of problems:
An immediate problem that prevents a product or service being provided adequately.
A person can have an idea that will enable the aims and objectives to be better achieved.
An information system analysis has to be undertaken when problems arise.

7. Other Change Factors
These factors often impose limitations and constrains on the design of the new system too
What other factors do you think would prompt for a change in IS?

8. Factors: Technical Economic Social and organisational
Legal and financial
Security and access factors
Health and safety

9. Technical Factors
Many transactions need to be processed each day.Examples:
TAB betting system
Stock market systems
Banking systems
Reliability
Robustness
Size of the network
Local processing
Type and amount of data
Legacy systems
Maintainability
Usability
Reliability:
Few breakdowns
The equipment will need to have redundancy built in (Fault tolerant systems)
Robustnes:
Operate in different physical conditions
Network size:
Mainframe as a server if too many nodes.
System needs to be scalable
Local processing:
If amount of processing small then only terminals could be required.
data:
Software and hardware will vary depending on the type of data
Legacy systems:
Keeping the old systems
Maintainability:
Grow according to organisation’s changing needs
Changes to hardware and software should be easily implemented
Usability:
Easy to use and simple to navigate and straightforward

10. Economic Factors
Initial cost in the selection of a design for a system
Ongoing cost:
Equipment upgrades and repairs
Cost of training and paying staff to run the system

11. Social and Organisational Factors
The needs of the user determine much of the design of an IS
The design should concentrate on the users’ needs rather than the processing and storage requirements

12. Legal and Financial Factors
In financial systems, the legal and accounting requirements can affect the way the system operates and its design.
There is a growing need for organisations to be able to communicate online (e-commerce)
There are also various legal requirements covering accounting and privacy matters. Back up and archiving procedures and equipment need to be taken into account.

13. Security and Access Factors
Logon names and passwords
Encryption
Biometric security
Keeping logs of activities
Surveillance cameras
Keys for locks
Smart cards
RFID transponders
guards

14. Security and Access Factors
Backup Security
A standard four week backup plan
Daily tape backups (reused each week)
Separate weekly tape backups reused monthly)
A monthly tape backup kept as permanent record

15. Security and Access Factors
Disaster Recovery Plans include:
Emergency power supply
Emergency procedures in case of fire, storms or natural disasters
Plans for replacement of or access to other computers and equipment
Procedures for restoring the data from backups stored in a safe place
Testing of the recovery procedures similar to a fire drill

16. Social Factors
All IS exist within a social context.
Considerations
Language
Audience
Purpose
Each organisation has its own culture that affects the design of IS and the flow of data and information.

17. Health and Safety Factors
Ergonomics arrangements
The use of voice recognition and voice production software
Use of robots and computer-controlled equipment in dirty and dangerous situations

18. Organisational Requirements
Many organisational factors can cause problems:
Number and location of branches
Types and conditions of buildings
Need to travel
Telecommunicating

19. Have you learned?
Analysis and Design worksheet
Question 6

20. Defining the Problem Exact problem has to be defined
A preliminary investigation is performed
The original problem is put in a negative form as it describes why a solution needs to be found.
Positive problem statements describe what needs to be done to fix the problem (It implies the goal/s to be achieved).
How do you think we can find the causes of the problem?

21. How much have you learned?
Analysis and Design worksheet
Answer questions 7a, 7b and 7c

22. Possible solutions
A feasibility study of the proposed solutions should be carried out.
Is the solution worthwhile?
Is the solution practical?
Three aspects to consider in the feasibility analysis are:
Operational feasibility
Technical feasibility
Economic feasibility

23. Possible solutions Operational Feasibility
Whether a project can be put into place.
How will people be affected.
Whether unintentional effects may occur as a consequence of the change
Legal and ethical issues are addressed
Effects on employment
Implementation schedules

24. Possible solutions Technical Feasibility
Characteristics of the required hardware and software:
Scalability for future needs
Reliability of the equipment
Whether the resources to operate the system exist
Availability of components

25. Possible solutions Economic Feasibility
If the new system is a good investment.
It will be feasible if benefits are more important than the costs of installing, planning, purchasing and building it.
The cost elements evaluated may include:
Personnel
Software licensing
Training
Development of custom-software
Cost of hardware

26. Choosing a solution A decision will be made based on the study
A feasibility report will be written presenting the consequences and benefits of the proposed solutions and the reasons for the final choice.
When the decision is made to proceed with the IS, limits and constrains are set on the system. It can include:
Money available
Time line of the project
Limitations of the changes within the organisation
Links between the new and old system

27. Case study
Ceep Kool case study

28. Analysis Phase
A detailed analysis of the old system is the basis for the design of the new one.
A logical design contains:
The broad aims and objectives of the new system
Major system components description
It is the basis of the physical design stage

29. Analysis Phase
A development team is selected, generally the Information System Department, user managers and potential system users.
The team is lead by a professional system analyst
Data is gathered using a number of techniques and analysed using a range of tools that will specify the data used, the information produced and the processes used to transform data into information.

30. Data Collection Techniques
It will come from documents and people associated with the IS, and people not directly linked to the IS: Customers and senior management.
Interviews
Observation
Surveys
Collection of documents and files
Research into similar and replacement systems

31. How much have you learned?
Answer questions 8 and 9

32. Tools used to describe IS
Two types of data are collected from the IS for the analysis:
Application data
Background data
Once collected, background data needs to be processed and manipulated by the development team to produce information.

33. Tools used to describe IS
The system analyst uses a number of tools to focus on three aspects of the system:
Logical operations involving data/information and the movement of data/information
The processing of data into information
The relationship between physical components of the information system.

34. Tools used to describe IS
Tools for analysing and documenting the logical operations of an IS are: CD
DFD
Data dictionaries

35. Tools used to describe IS
Tools for analysing and documenting the processing of data and information are:
Flowcharts
Decision tables
Decision trees
Grid charts
Structured English
IPO charts
Processing centre descriptions

36. Tools used to describe IS
Tools for analysing and documenting the relationship between the physical components of an IS, both hardware and software, are:
Hierarchy charts
Structure charts
System flowcharts