Scope and Coverage. Learning Outcomes. V1.0 Visuals Handout Page 1. This topic will cover: By the end of this topic, students will be able to:

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1 Topic 11: Needs Analysis Needs Analysis Topic Scope and Coverage This topic will cover: Client and system requirements Investigation/analytical techniques Problems/limitations obe o s with current/new e system, Functionality, costs, timescales, resources Case study Introduction Needs analysis exercise Needs Analysis Topic Learning Outcomes By the end of this topic, students will be able to: Produce a system design specification to meet a client s needs Visuals Handout Page 1

2 Needs Analysis Topic Systems Development Life Cycle - 1 The Systems Development Life Cycle (SDLC) consists of a number of stages: Initiation System concept development Planning Requirements analysis Design Needs Analysis Topic Systems Development Life Cycle - 2 Development Integration and testing Implementation Maintenance (operational stage) Termination These stages are done within a project. Needs Analysis Topic Project Management Phases - 1 Developing a new computer system involves the management of a project. Project management covers the following phases: Planning Implementation Delivery Support Monitoring Visuals Handout Page 2

3 Needs Analysis Topic Project Management Phases - 2 There may be variations in both the SDLC and project plan depending on the nature of the project. There are a number of standard approaches to both SDLC and project planning. Needs Analysis Topic Requirements (or Needs) Analysis This is the process of finding out what the user/customer/client needs from the new system. There is an entire field of study covering Needs Analysis. We shall just present the key steps in a basic approach in this module. Requirements Elicitation Needs Analysis Topic Obtaining the requirements for the computer system from stakeholders Certain issues affect the success of requirements elicitation: Unclear mission Misalignment of understanding and different agendas Changing requirements Understanding (or otherwise) of technology Visuals Handout Page 3

4 Requirements Elicitation Recommendations - 1 Needs Analysis Topic Ian Sommerville ( and Roger Pressman ( have produced the following recommendations: Establish that a project is feasible. Understanding whether data collection may be affected by personal agendas. Identify the people who hold vital information. Establish the technical environment in which the system will operate. Requirements Elicitation Recommendations - 2 Needs Analysis Topic Decide which methods will be used for data collection. Ensure that prototyping is used to address interim problems. Guarantee the participation of stakeholders throughout the process. Evaluate the prototypes by establishing realistic use scenarios. Requirements Negotiation Needs Analysis Topic It is not always possible to establish all the requirements in initial meetings. Agendas may change. New requirements may arise. There may be confusion between parties. E.g. users vs. management External factors (e.g. legislation) may impact the project. Time and cost may impact the project. It is necessary to maintain a dialogue between the developers and the users. Visuals Handout Page 4

5 Needs Analysis Topic Priorities In any project, it is necessary to establish priorities: Essential Desirable Possibly based on timescales: Essential in this version Desirable in this version, but essential at some future time Desirable in some future version Possibly based on cost: Essential irrespective of cost Desirable if we can afford it Requirements Management Needs Analysis Topic A series of stages similar to an SDLC: Tracing the requirement life history Investigating the requirements Feasibility study Design the system based on the requirements. Testing against realistic scenarios Proof of concept prototypes Monitoring how the system has met the requirements Types of Requirements Needs Analysis Topic Functional - used to judge whether particular functions are performed by the system) E.g. implementation of an online transaction module for a website. Non-functional - associated with generic behaviour of the system and may relate to quality issues E.g. may relate to the ease of use for a peripheral device. Success criteria may be identified in terms of performance, quality assurance, or adherence to design standards. Visuals Handout Page 5

6 Needs Analysis Topic Stakeholders Stakeholders are individuals or groups who have an interest or involvement in the system. Primary stakeholders are directly using the system. Secondary stakeholders may not be using the system, but are directly affected by its operation. Tertiary stakeholders have some lesser interest or a concern for the system and its operation. Example Stakeholders Needs Analysis Topic Users of a computer system Managers who control resources being affected by the new systems Governments deploying particular technologies Communities that may be impacted by the system Customers who may expect additional services Investors who want a return Employees whose jobs are affected Determining Needs Needs Analysis Topic There are a number of techniques to determine the needs of a system: Observation of current system Questioning of current users Questionnaire or interview Questioning of current management Questionnaire or interview Studying background information E.g. new legislation, supplied documentation Visuals Handout Page 6

7 Needs Analysis Topic Problems with Current System - 1 If you are replacing a current system (either manual or computer-based) then you need to identify the current problems that you hope to solve with the new system. Are you aiming to: Increase capacity? Reduce time taken to do a job? Reduce costs, increase profits or both? Reduce space (e.g. file storage)? Improve service? Needs Analysis Topic Problems with Current System - 2 Reduce environmental impact, e.g. power consumption? Provide new functionality? Fix specific problems? Needs Analysis Topic Efficient Do NOT just say improve efficiency. Say what area you are hoping to make more efficient, e.g. You may reduce time taken, but at the expense of using more power. You may provide an improved service, but require more staff, which increases costs. Visuals Handout Page 7

8 Needs Analysis Topic New System Limitations Your new system will not automatically solve all your problems. Clearly identify what the new system does solve. Clearly identify what it does not solve. Say why the new system does not solve these problems. Identify possible solutions to remaining problems. Provide indications of feasibility and costs to solve remaining issues. Needs Analysis Topic Result of Needs Analysis By the end of the Needs Analysis phase, you should know: Who will be using the system? How will the system be used? What should the system do? What will the system not solve? How will the system achieve its aims? For how long is the system going to be used? What will be the boundary of the system (i.e. with what other systems it will interact?) Needs Analysis Topic Avoid Over specifying - There is a tendency to look at any computer system requirement and just put in the most powerful system you can afford. This is not the best approach. Match the system to the requirements. Match the system to the users. Match the system to the environment in which it will be used. Match the system to the resources available. Visuals Handout Page 8

9 Needs Analysis Topic Documentation - 1 Many organisations will have a standard template for needs analysis. This provides a framework for documenting the system requirements. It also provides a guide to determining the requirements in an organised way. Needs Analysis Topic Documentation - 2 Most government organisations and many larger businesses will require the use of their template as part of the formal project management process. An example is available at Needs Analysis Topic Sources Ian Sommerville ( Roger Pressman ( Example requirements documentation template: Visuals Handout Page 9

10 Needs Analysis Topic Any Questions? Visuals Handout Page 10