SSADM

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SSADM

• Structured Systems Analysis and Design Methodology

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Life Cycle Phases

• Planning
• Feasibility Study
• Analysis
• Design
• Code and Unit test

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3
Stages

• 0. Feasibility
• 1. Analysis - Current systems and problems /
• requirements
• 2. Business system option
• 3. Define requirements - specify
• 4. Technical Systems Options
• 5. Logical system design
• 6. Physical system design

4
Feasibility

• Prepare for feasibility study
• Define the problem
• Select Feasibility Options
• Assemble Feasibility Report

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010 Prepare for feasibility study.

• Context Diagram
• Current Physical Level-1 DFD
• Overview LDS (Logical Data Structure)
• Requirements Catalogue
• i.e. a list of all requirements

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020 Define the problem.

• Outline current and required environment
  description
• Requirement catalogue
• User Catalogue
• Problem Definition Statement

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Feasibility

• 030 Select Feasibility Options
• Action Plan
• Feasibility options
• 040 Assemble Feasibility report
• Feasibility study report

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Investigation of Current Environment

• 110 Establish Analysis framework
• Requirements catalogue
• Context diagram
• Current Physical DFD, level 1
• Overview LDS
• Agreed Systems Analysis and Design Method
• 120 Investigate and define requirements
• Requirements catalogue
• User Catalogue
• 130 Investigate current processing
• Context diagram
• Current physical DFM

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• 140 Investigate current data
• Current Environment LDM
• 150 Derive logical view of current services
• Context diagram
• Logical Data Store / Entity Cross-Reference
• Logical DFM
• Requirements Catalogue
• Current Environment LDM
• 160 Assemble Investigation Results
• Current Services Description
• Requirements Catalogue
• User Catalogue

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Data Store / Entity Cross-Reference

• This is a matrix, with data stores across the top
  and entities down the side.

Data Store / Entity Diary Dog Chart Journal
Payment X
Dog X X
Stay X X
Owner X
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Business System Option

• 210 Define Business System Options
• 220 Select Business System Option

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Requirements Definition

• 310 Define required system processing
• Required system Logical LDM
• User Roles
• 320 Develop Required Data model
• Produces the Required system LDM
• 330 Derive System Functions
• I/O structures
• User Role/Function Matrix
• Function Definitions

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• 340 Enhance Required Data model
• Required system LDM
• 350 Prototype I/O Interface
• Menu and command structures
• Prototyping report
• 360 Develop Processing Specification
• Required system LDM
• ELHs
• ECDs (Effect correspondence diagrams)
• EAPs (Enquiry access paths)

14

• 370 Confirm System objectives
• Function Definition
• Required System LDM
• 380 Assemble Requirements Specification
• Requirements Specification

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Technical Systems Options

• 410 Define TSOs
• 420 Select TSO

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Logical System Design

• 510 Design user dialogues
• Dialogue structure
• Dialogue-level help
• Dialogue control table
• Menu Structure
• Command structure
• 520 Define update processing
• ELHs
• Entity Descriptions
• Update Process Models
• 530 Define Enquiry Processing
• Enquiry Process Models
• 540 Assemble the Logical Design
• Logical Design

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Physical System Design

• 610 Prepare for Physical design
• Application Development Standards
• 620 Create Physical data design
• First cut Physical data design
• 630 Create Function component Implementation map
• FCIM
• Function definitions
• 640 Optimise Physical Data design
• Function Definitions
• Physical Data design, optimised
• Space estimation
• Timing Estimation 

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• 650 Complete function specification
• FCIM
• Function definitions
• 660 Consolidate Process Data Interface
• FCIM
• Function definitions
• 670 Assemble Physical Design
• Physical Design