1. Foundations of Information Systems Topic 8 Acquisition and development of Information systems

2. Learning objectives After this lecture, you will be able to:  evaluate the different alternatives for acquiring IS;  distinguish between the typical stages involved in building IS;  explain the purpose of each stage in building a system;  select the best alternative type of approach or methodology for building a IS.

3. Introduction to IS acquisition  the different approaches 4 IS Acquisition  Off the Shelf Approach  Bespoke Development  End User development  the different methodologies for IS development  Waterfall model  Prototyping  Incremental  Spiral  Rapid Application Development (RAD)  Other software development approaches

4. Introduction to IS acquisition  IS acquisition - The process of obtaining an IS for a business.  There are different approaches to the acquisition of IS systems as well as methodologies as seen in the previous slide.

5. Drivers for IS acquisition

6. Typical evaluation of alternatives for IS acquisition

7. Bespoke development  Bespoke development: An IS is developed ‘from scratch’ by an IS professional to suit the business requirements of the application.  Benefits:  Tailored to requirements of business  May confer specific competitive advantage  Problems:  Expense  Time  Quality

8. Bespoke Development A. In sourcing  IT specialists within your organization will develop the system.  The internal entity will usually have a specialized team who will be proficient in the providing the required services.  Organizations sometimes opt for in sourcing because it enables them to maintain a better control of what they outsource.

9. Advantages of in sourcing  Many organisations have own specialists for software maintenance and development.  Confidential information or ideas are kept within the organisation.(secure)  Cheaper  Skills development

10. Disadvantages of insourcing  Developing a major new system may require extra staff with specialised skills. Such people may be difficult to recruit, especially for a short time.  It takes your company's focus away from core business activities N.B. A Company may prefer to bring in outside consultants

11. B. OUTSOURCED  What is outsourcing?  It is hiring an outside company to handle all or part of an organization’s bis aquistion.  the delegation of specific work to a third party for a specified length of time, at a specified cost, and at a specified level of service.  In a mainframe outsourcing agreement, the outsourcers buy their client’s computers and hire all or most of the client’s employees.

12. Outsourcing

13. Outsourcing Advantages  Asset utilization  Access to greater expertise and more advanced technology( leading-edge technology).  Lower costs  Improved development time(Shorter implementation cycles).  Facilitation of downsizing  Focus on unique core competencies.  Exploit the intellect of another organization.  Improve performance accountability.

14. Outsourcing Disadvantages  Reduces technical know-how for future innovation.  Reduces degree of control.  Increases vulnerability of strategic information.  Increases dependency on other organizations.  Contract problems.  Loss of control of system and/or data  Reduced competitive advantage  Possibility of poor service  Inflexibility

15. USER DEVELOPED SYSTEMS  Development of information systems by end users with little or no formal assistance from technical specialists  Allows users to specify their own business needs  Also called knowledge worker development, end user development or end user computing  The same as self-sourcing

16. Self sourcing Advantages  Gives users control over both the development of an application and the ongoing maintenance  No need to explain user requirements to IS analysts  Gives users control over the development budget  Results in the possibility of greater user acceptance  Improves requirements determination.  Increases knowledge worker participation and sense of ownership.  Increases speed of systems development.

17. Self sourcing Disadvantages  Difficult to evaluate end-user development activities  Lack of documentation and external support leads to short- lived systems.  Security may be breached  Inadequate knowledge worker expertise leads to inadequately developed systems.  Lack of organizational focus creates “privatized” IT systems.  Insufficient analysis of design alternatives leads to haphazard IT systems.

18. OFF THE SHELF SYSTEMS  Off-the-shelf: Direct purchase of a pre-written application used by more than one company.  These can be tailored or standard Benefits:  – Time – Quick purchase  – Cost – Low cost due to economies of scale  – Quality – Should offer stability and be feature-rich Disbenefits:  – May omit some features specifically required by individual customer  – Requires changes to process to meet needs of software

19. Application complexity versus uniqueness

20. Summary – acquisition alternatives

21. Systems development lifecycle (SDLC) :  Any information systems project follows a logical series of development phases. These are known as the systems development lifecycle.  In the beginning there were no defined stages that people would follow in information system development - The situation was chaotic. Systems built:-  would take long to be build.  were expensive.  would not meet all users requirements.  would contain a lot of errors.  SDLC stages : Initiation, feasibility assessment, system analysis, systems design, system build, implementation and maintenance.

22. SDLC Go Back to a previous Stage or Stop (1) Initiation (2) Feasibility assessment (3) Systems Analysis (4) System Design (5) System Build (6) Implementation (7) Maintenance A 7-stage systems development life cycle (SDLC)

23. Initiation phase  The startup phase in an IS development project.  Its aims are to recognize a problem or opportunity and try to brainstorm on the possible  Input: creative thought and/or systematic evaluation of IS needs.  Output: idea for initiation of a new information system.

24. Feasibility assessment  An activity at the start of the project to ensure that the project is a viable business proposition.  Trying to find out if the selected project is feasible and then prepare to ensure that the project is successful.  The feasibility report analyses the need for and impact of the system and considers different alternatives for acquiring software.

25. Feasibility assessment Feasibility of the system is divided into :-  Technical feasibility  Economic Feasibility  Operational feasibility  Schedule Feasibility Input: idea for initiation of a new information system. Output: feasibility report and recommendation to proceed.

26. Systems analysis  The capture of the business requirements of a system from talking to or observing end users and using other information sources such as existing system documentation.  Defines what the system will do.  Input: terms of reference in feasibility report describing outline requirements.  Output: detailed Requirements specification summarizing system functions.  Supported by diagrams showing the information flow and processes that are required. (DFD,ERD,ELH)

27. Systems design  Defines how the system will work in key areas of user interface, program modules, security and database structure and transactions.  Questions to answer  How can the user requirements understood in analysis stage be translated into an information system?  What technologies( software and hardware) will be used for construction and Implementation?  Input: Requirements specification.  Output: detailed design specification.

28. System build  Describes the creation of software by programmers.  It involves writing the software code (programming), building release versions of the software, constructing and populating the database and testing by programmers and end users.  Writing of documentation and training may also occur at this stage.  Input: requirements and design specification  Output: working software, user guides and system documentation.

29. System implementation  Involves the transition or changeover from the old system to the new and the preparation for this, such as:  making sure the hardware and network infrastructure for a new system are in place;  testing the system; and also human issues of how best to educate and train staff who will be using or affected by the new system.  Input: working system, not tested by users.  Output: signed off, operational information system installed in all locations.

30. System Maintenance  Monitor and support the new system to ensure it continues to meet the business goals.  Help desk to support the system users.  Provide an environment to support system changes.  Debugging the program  Updating the system to accommodate changes in business conditions  Add new functionality to the system  System Audit.

31. Why Systems Fail  Many systems fail because of the following, 1. Unclear or missing requirements 2. Skipping SDLC phases 3. Failure to manage project scope (scope creep and feature creep) 4. Failure to manage project plan 5. Changing technology 6. Poor monitoring and control of progress 7. Changes in culture, funding, or objectives 8. Use of no or poor estimating techniques 9. Personality conflicts and employee turnover 10. Unrealistic cost estimates

32. Alternative to sdlc  Other methodologies  Prototyping  Rapid Applications Development (RAD)  Joint application development  Spiral model  Capability Maturity Model for Software (CMM or SW – CMM)  Dynamic Systems Development Methodology (DSDM)

33.  Process of building experimental system quickly and inexpensively for demonstration and evaluation  Prototype - a model of a proposed product, service, or system.  Proof-of-concept prototype - used to prove the technical feasibility of a proposed system.  Selling prototype - used to convince people of the worth of a proposed system. PROTOTYPING

34. Prototyping

35.  Speeds up the development approach  Helps sell the idea of a proposed system  Gives the users the opportunity to clarify their information requirements  Gives users a feel for the final system.  Helps determine technical feasibility.  Encourages active knowledge worker participation.  Helps resolve discrepancies among knowledge workers Prototyping Advantages

36.  Replaces the systematic analysis and design stages of the SDLC - quality may be sacrificed  Can result in an excess of iterations  Leads people to believe the final system will follow shortly.  Gives no indication of performance under operational conditions.  Leads the project team to forgo proper testing and documentation. Prototyping Disadvantages

37. Rapid Applications Development (RAD)  A method of developing information systems that uses prototyping to achieve user involvement and faster development compared to traditional methodologies such as SSADM.  Uses minimal planning in favor of rapid prototyping. The "planning" of software developed using RAD is interleaved with writing the software itself.  The lack of extensive pre-planning generally allows software to be written much faster, and makes it easier to change requirements

38. Joint Application Design (JAD)  The Joint Application Development (JAD) methodology aims to involve the client in the design and development of an application.  Users, Managers and Analysts work together for several days  System requirements are reviewed  Structured meetings

39. Spiral model  An iterative systems development model in which the stages of analysis, design, code and review repeat as new features for the system are identified  The four main activities of this model are:  Planning. Setting project objectives, defining alternatives.  Risk analysis. Analysis of alternatives and the identification and solution of risks.  Engineering. Equivalent to the build phase of the SDLC with coding and testing.  Customer evaluation. Testing of the product by customers.

40. Boehm’s spiral model of systems development

41. Dynamic Systems Development Methodology (DSDM)  A methodology that describes how RAD can be approached.  1. Active user involvement is imperative.  2. DSDM teams must be empowered to make decisions.  3. The focus is on frequent delivery of products.  4. Fitness for business purpose is the essential criterion for acceptance of deliverables.

42.  5. Iterative and incremental development.  6. All changes during development are reversible.  7. Requirements are base lined at a high level.  8. Testing is integrated throughout the lifecycle.  9. A collaborative and co-operative approach between all stakeholders is essential. Dynamic Systems Development Methodology (DSDM)

43. Thanks 4 listening