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Analysis Phase

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• The Analysis Phase • System Requirements• Models and Modelling of requirements • Stakeholders as a source of requirements

Lecturer details

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Activities of Analysis Phase

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Activities 1: Gather Information

Gathering information involves: • Understanding the existing system• Identifying all current and future users, locations, system interfaces (inside and outside the organization)• Identifying possible software package solutions that might be used

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Activities 2: Prioritize Requirements

Prioritize Requirements• Establish which functional and technical requirements are most critical

Why prioritize• Because resources are always limited and you want to address the most important things

• System requirements tend to expand as users make more suggestions (called “scope creep”)

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Activities 3: Prototype for Feasibility and Discovery • If system involves new technology, the team may need to get experience working with it. Creating prototypes can be very valuable

• Prototyping helps to understand possibilities and limitations of the technology

• By showing prototypes to end users can get feedback into what is really needed

• Prototypes help users (and analysts) to discover requirements they might not thought about otherwise

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Activities 4: Generate and Evaluate Alternatives

• Could include considering more than one method to develop system• Could involve in-house development or outsourcing to a consulting firm• Might be able to use “off the shelf” software package• Each alternative has costs and benefits to be considered

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Activities 5: Review Recommendations with Management

• Usually done when all the above are completed

• Must decide if project should continue at all

• Must decide on which alternative is the best

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Systems Requirements

• System requirements – specifications that define the functions of the new system

Two sets of requirements:Functional requirementsNonfunctional requirements

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Functional and Non-Functional Requirements

Functional requirementsActivities system must perform (use cases)Based on procedures and business functionsDocumented in analysis models

Non-functional requirements Technical requirement – hardware and softwarePerformance requirement – workload measuresUsability requirement – user interface, workflowReliability requirement – outages, error detectionSecurity requirement – access & protection

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Models and modelling

•Requirements are describes by a collection of models• Reasons for modelling

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Types of Models

Different types of models are used in information systems development

Mathematical – formulas that describe technical aspects of the system (e.g., processing rules)

Descriptive – narrative memos, reports, or lists that describe aspects of the system

Graphical – diagrams and schematic representations of some aspect of the system

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Requirement model examples

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Stake Holders, the source of requirements

People with interest in successful system implementation

Three primary groups of stakeholders

Users (use system)

Clients (pay for and own system)

Technical staff (ensure system operation)

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Stakeholders Interested in New System

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The transition from information gathering to model

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End

Thank you

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