1. Software Engineering: A Practitioner’s Approach, 6/e Chapter 3 Prescriptive Process Models

2. SW Process Models It is a set of activities required to:
Prescriptive process models advocate an orderly approach to software engineering.
It is a set of activities required to:
Define, design, implement, test and maintain a software product.
A SW process model is chosen based on the nature of the project.

3. SW Process Model Phases
All models have phases and each phase has 3 components:
Set of activities, this is what you do.
Set of deliverables, this is what you produce.
Quality control measures, this is what you use to evaluate the deliverables.
The activities defines the process Framework, the generic set encompasses:
Communication, planning, modeling, construction, and deployment

4. The Waterfall Model
This Model suggests a systematic, sequential approach to SW development that begins at the system level and progresses through analysis, design, code and testing.

5. Waterfall Model Advantages Disadvantages
Easy
Structured
Provide a template into which methods for analysis, design, code, testing and maintenance can be placed.
Disadvantages
Sequential, does not reflect reality
Does not allow for feedback
Does not produce a prototype
User must wait until the end to see the final program.

6. When to use the Waterfall Model
Simple Projects
Limited amount of time
Requirements are well understood
We can use it for our Class Project.

7. Incremental Models
Goal to provide quick basic functionality to the users
Process is not linear
Requirements are well defined
Software is completed in an increments fashion
Will Study 2 models:
Incremental Model
RAD

8. Incremental Model
It combines characteristics of the waterfall model and the iterative nature of the prototyping model.
1st build is usually the CORE product
Each increment “deliverable” may add a new functionality.
This is repeated until the product is complete

9. The Incremental Model Communication Planning Modeling Construction
Deployment

10. When to Use the Incremental Model
When staffing is not available by deadline.
When the software can be broken into increments and each increment represent a solution

11. The Rapid Application Development RAD Model
Builds on the Incremental model with emphases on short development cycle.
In other words high speed waterfall model
Components are build using this model as a fully functional units in a relatively short time
It assumes that the system can be modularized
RAD will fail if you don’t have strong and skillful teams
High performance might be an issue

12. The RAD Model

13. Evolutionary Process Models
Core requirements are well understood but additional requirements are evolving and changing fast
Time-to-Market
Iterative – software gets more complex with each iteration
Prototype
Spiral
Concurrent

14. Evolutionary SW Process Models
Advantages
Do not require full knowledge of the requirements
Iterative
Divide project into builds
Allows feedback, show user something sooner
Develop more complex systems

15. Prototyping Model Start with what is known about requirements.
Do a quick design.
Build the prototype by focusing on what will be seen by the user.
Use the prototype to show the user and help refining requirements.

16. Evolutionary Models: Prototyping
Quick
plan
communication
Modeling
Quick design
Deployment
delivery &
feedback
Construction
of prototype

17. When to Use Prototype Model
When the customer define general objectives for the SW but does NOT identify details about INPUT, OUTPUT, or processing requirements.
The developer is unsure of the efficiency of an algorithm, human machine interaction, etc.

18. Prototype Model Advantages
Prototype is served as the machinery for identifying requirements.
Is developed very quick.
Disadvantages
Customer might think that the prototype is the final product and forget lack of quality i.e PERFORMANCE, RELIABILITY.

19. Spiral Model
Iterative (like Prototype) and controlled (like waterfall) model.
Software is developed using evolutionary releases
Software complexity increase with each release

20. Spiral Model Consist of 6 task regions.
Customer communication - the goal is to establish good communication between customer and developer.
Planning - produce/adjust project plan.
Risk analysis - assess management and technical risks.
Engineering - build one or more representations of the application.
Construction and release - - to construct, test, install and support the application.
Customer evaluation – get customer feedback.

21. Evolutionary Models: The Spiral

22. When to Use the Spiral Model
Very large projects.
When technical skills must be evaluated at each step.

23. Component based development
The process to apply when reuse is a development objective
Evolutionary
COTS are used to build software
Steps:
Identify candidate components
Design each using and model or OO classes
Component integration
Architecture
Testing

24. CBD
component-based development (CBD) model incorporates many of the iterative characteristics of the spiral model.
The main difference is that in CBD the emphasis is on composing solutions from prepackaged software components or classes

25. Process Models
AOSD—provides a process and methodological approach for defining, specifying, designing, and constructing aspects

26. Unified Process
a “use-case driven, architecture-centric, iterative and incremental” software process closely aligned with the Unified Modeling Language (UML)
Tools are used to describe customer views (use cases)
Used mainly for OO based methodologies
Runs in phases

27. The Unified Process (UP)
inception
Phase 1
Communication + Planning
Phase 2
Planning + Modeling
elaboration
inception
Phase 3
Coding, unit test & integrate Components
result
Phase 4 Deployment

28. UP Phases

29. UP Work Products

30. BackUp

31. Project
Day Care Center

32. Child Care Center for NCC
Your company has been awarded a contract to develop Child Care Software for Neñios Care Center (NCC).  The software should maintain a database of Family, Child, and Payroll information.  Users of the software shall have the ability to add/update/delete all information based on their access levels.  All employees (teachers, admin staff, etc.) will be identified by a unique login ID and given a default password. The employee first and last name should be stored

33. Child Care Center for NCC
The general requirements for the software are as follows:
Any change in the database (add or update) the user ID and time of change should be stored on the record.
The system must respond to all requests within 20 seconds.
A web-based solution is optional.
The ability for an employee to update the password is optional.
The software shall support the ability to store, update, maintain, and delete of Family & Child Information, Family and Child Billing, and Payroll information as specified in Amendment A.

34. Family and Child Information
Store and track child, parent and family information Data including but not limited to:
Parent names, addresses, phone numbers, addresses, emergency contacts, authorized pick ups, etc.
Child Name, Birth Date, Class, Special Needs, Photo, etc.
Immunization tracking information: recording immunization types, physicals and dates
Classroom Tracking & Scheduling
Classrooms, programs, activities, schedules, etc
Immunization Software, Alerts you when an immunization is needed and prints reports showing immunization dates and immunization due notices for parents.
Waiting List & Potential Customer Tracking

35. Family and Child Information
cont
Daily Reminders, upcoming appointments, contract renewals, etc.
Customer Log Notes, Maintain records of correspondence with parents, child's special needs, incident reports, and more.
Reports:
Call Sheets, Sign In & Out Sheets
Customer Directories
Daily Classroom & Center Enrollment Reports
Birthday Lists & Child Age Reports
Parent/Child Cross Reference Reports
Family Registration Information
Immunization Due & History Reports
Child Enrollment/Withdrawal Reporting
Child Notes & Comments Reports

36. Family and Child Billing
track each family’s balance including their child care billing history of registration fees, tuition charges, family discounts and payments received
Billing History, history of registration fees, tuition charges, family discounts and payments.
Late Fees & Balance Due Notices, late payment fees and print balance due notices to all families who are past due.
Receipt Printing
Reports: Customer Account Balance (Notice)
Account Activity Report
Billing of tuition based on actual attendance (Attendance Tracking).
Overtime and hourly billing for late pick ups and extra hours

37. Payroll Pay check, Overtime Withholds and tax information Reports
Calculates pay period hours, determines gross pay, applies all withholdings, and prints checks
Overtime
Withholds and tax information
such as state, federal,FICA
Reports
Employee Earnings Withholdings Summary (W2)
Total Revenue Reports

38. Security Login is required for all users
Users can be divided into groups and access is granted on a per group basis
for example you may want to allow only the managers group to view, update, or delete payroll information)

39. Backup Sliddes

40. Evolutionary Models: Concurrent
State tracking for each framework activity
Defines a network of concurrent activities
Actions cause state changes in one or more activities
action