Inception, analysis and design overview

Part 3-Inception
2
Objectives
What we will learn:
Define the inception step.
3
Purposes of inception
The intent of inception is:
Establish some initial common vision for
Objectives of the project,
Determine if it is feasible, and
Decide if it is worth some serious
Investigation in elaboration.
4
Example questions in Inception
For example, you need to ask questions such
Are already ed:
What is the vision and business case for this
Project?
Feasible?
Buy and/or build?
Rough estimate of cost: Is it $10 K-100 K or
In the millions?
Shocould we proceed or stop?
5
What artifacts (WP) may start in Inception?
Describes the functional requirements, and related
Non-functional requirements.
Use-case model
Comment
Artifact
Describes the High-level goals and constraints,
Business Case, and provides an executive summary.
Vision and
Business Case
Prototypes and to clarify the vision, and validate technical ideas.
Proof-of-Concepts
Describes the business, technical, resource, schedule,
People, education, and other resources, risks control
Project
Management Plan
Describes risks (the business, technical, resource,
Schedule), and ideas for their mitigation or response.
Risk list & risk
Management Plan
Glossary key domain terminology
6
Requirements artifacts
Vision
Supplementary
Specification
Software
Architecture Doc.
Glossary
Domain
M o d e l
Requirements
Project
Management
Business
Modeling
Design
Partial A rtifa CTS,
Refined in each
Iteration.
T e S t
T e S t
P L A N
Software
D e v. P L A N
Design Model
*
*
U s e-C A S E
M o d e l
Environment
Development
C A S E
7
You know you didn't understand inception when...
It is more than "a few" weeks long for most projects.
There is an attempt to define most of the requirements.
Estimates or plans are expected to be reliable.
You define the architecture (this shocould be done iteratively
In elaboration ).
You believe that the proper sequence of work shoshould be: 1)
Define the requirements; 2) design the architecture; 3)
Implement.
There is no business case or vision artifact.
All the use cases were written in detail.
None of the use case were written in detail; rather,
1020% shoshould be written in detail to obtain some realistic
Insight into the scope of the problem.

Analysis and design overview
2
Objectives: analysis and design overview
Review the key analysis and design terms
And concepts
Introduce the analysis and design process,
Including roles, artifacts and workflow
Explain the difference between Analysis
And Design
3
Analysis and Design in context
The purposes of analysis and design
Are:
Transform the requirements into
Design of the System-to-be.
Evolve a robust architecture for
System.
Adapt the design to match
Implementation environment,
Designing it for performance.
The purposes of analysis and design
Are:
Transform the requirements into
Design of the System-to-be.
Evolve a robust architecture for
System.
Adapt the design to match
Implementation environment,
Designing it for performance.
4
Supplementary
Specification
Use-case model
Design Model
Data Model
Architecture
Document
Analysis
And Design
Analysis and design overview
Glossary
5
Analysis versus Design
Focus on understanding
The solution
Operations and attributes
Performance
Close to real code
Object lifecycles
Nonfunctional
Requirements
A large Model
Focus on understanding
The Problem
Idealized Design
Behavior
System Structure
Functional requirements
A small model
Analysis Design
6
Design classes
Subsystems
Use Cases
Analysis and design are not top-down or bottom-up
Analysis classes
Bottom
Up
Top
Down
(Define
Middle level)
Analysis and Design
7
What is architecture?
Software architecture encompasses a set
Significant decisions about the organization
Of a software system.
Selection of the structural elements and their
Interfaces by which a system is composed
Behavior as specified in collaborations
Those elements
Composition of these structural and behavioral
Elements into larger subsystems
Invalid tural style that guides this Organization
Grady booch, Philippe kruchten, rich reitman, Kurt bitpattern; rational
(Derived from Mary Shaw)
8
Architecture constrains Design and Implementation
Architecture involves a set of strategic
Design decisions, rules or patterns that
Constrain design and construction.
Architecture decisions are the most fundamental
Decisions, and changing them will have significant effects.
Architecture
Design
Implementation
Code
9
Software Architecture: the "4 + 1 View" model
Process view
Deployment View
Logical view
Use-case View
Implementation View
End-user
Functionality
Programmers
Software management
Performance, scalability, throughput
System integrators
System topology, delivery,
Installation, Communication
System Engineering
Analysts/designers
Structure
10
Analysis and Design Workflow
Analysis
Design
[Early elaboration
Iteration]
[Inception Iteration
(Optional)]
Define a candidate
Architecture
Perform
Architectural
Synthesis
Analyze behavior
Refine
Architecture
Design
Components
Design
Database
(Optional)
11
Analysis and design activity Overview
Effecect
Designer
12
Software effecect's Responsibilities
Effecect
Software
Architecture
Document
The software
Architect leads
And
Coordinates
Technical
Activities and
Artifacts.
Reference
Architecture
Analysis Model
Design Model
Implementation Model Deployment model
13
Designer's Responsibilities
Designer
Use-case
Realization
Package class/subsystems
The designer
Must know usecase
Modeling
Techniques,
System
Requirements,
And Software
Design
Techniques.
14
Review: analysis and design is use-case driven
Use Cases defined for a system are
Basis for the entire development process.
Benefits of use cases:
Concise, simple, and understandable by a wide range
Of stakeholders.
Help synchronize the content of different models.
Withdraw money
Check balance
Customer
15
What is a use-case realization?
Use Case class diagrams
Communication
Diagrams
Use-case Model Design Model
Use Case use-case Realization
Sequence
Diagrams
16
Analysis and Design in an iterative process
Iteration n iteration n + 1
Use Case
Scenarios 1 & 2
Use-case
Realization
Start of iteration
End of iteration
Use Case B
Scenario 1
Use-case
Realization
Use Case
Scenario 3
Use-case
Realization B
17
Review: analysis and design overview
What is the purpose of the analysis and
Design discipline?
What are the input and output artifacts?
Name and briefly describe the 4 + 1 views
Architecture.
What is the difference between Analysis
And design?
What is architecture?