Sdlc - Extreme Programming

Software Development Life Cycle The “Alternative” Models

Group: OTUB Duncan Belser Jose Ferreira Sandra Hung Brett Lake

Do Traditional SDLC Models Work Today? 

Answer: Not all the time

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Why?   

Traditional models are not flexible Systems are too big and complex Many players involved 

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i.e., 2,000+ people involved w/ MS Windows 2000

Rapidly changing technology Time is critical (develop / implement / market ) Globalization

Alternative SDLC Approaches Extreme Programming Method

1. 

Kent Beck, 1996

Synchronize and Stabilize Method

3.  

David Yoffie (Harvard) Michael Cusumano (MIT)

1. Extreme Programming (XP) Purpose: Develop faster and under budget Key Principles: Simplicity, Communication & Feedback Basic Practices:  Short development cycles  Small code releases  Frequent testing  Customer involved in development process  Customer stories  Simple programming and documentation  Pairing programmers – collaboration

1. XP: (Symantec  Testing XP vs. Waterfall model Example) “To improve productivity, performance, quality”  

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Outcome   

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Project: Develop Java-based security product Increased productivity – software in 2 weeks Radical decrease in bugs – only 5 bugs at beta Team mentality – “not just cogs in a machine”

Problems 

  

Pairing programmers causes conflicts Roles and responsibilities are still unclear Culture conflict XP does not address deployment

2. Synchronize & Basic Stabilize Concept Method 

Continually synchronize what people are doing as members of parallel teams



Periodically stabilize the product in increments as a project proceeds

How it Works:  Requirements analysis – interview customers 

Draw up product specifications



Divide project into 3 to 4 builds

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Synchronize (test & bug) – at end of day

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Stabilize (fix & freeze build) – at end of build

2. Synchronize and Stabilize Method Microsoft Way: 

Customer-driven projects

NG

EN VI

Combination 

Vision Approved

DE

Waterfall & Spiral Model

Scope Complete

N

PI N

O

A phase-based, milestone-driven, and iterative model.

L



NI

VE

NG



G NI N

STA

ZI LI

O SI

i.e., Win95/98 BI



Release

PL

G

A

Project Plan Approved

MSF Application Development Process Model

2. Synchronize and Stabilize Method  The key issues of MS’s success 

Determine documentation baseline early, freeze it late

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Set Interim milestones early

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Segment large work efforts into manageable pieces

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Work closely with the early adaptors

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Versioned releases principle select critical rather than desirable pieces in a shorter time frame

So What Model Works Best? 

It Depends!!! 



On the project, corporation, time frame, etc…

Take a Tailored Approach 

Project managers customize models to fit the projects specific needs

Questions

References  

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Wallace, B. (Jan. 18, 1999). Ford to retool app development. COMPUTERWORLD [Online]. Available: www.computerworld.com/news/1999/story/0,11280,33624,00.html King, J. (June 10, 1996). Vendors feed user frenzy for rapid application development. COMPUTERWORLD [Online]. Available: www.computerworld.com/news/1996/story/0,11280,5807,00.html Morales, A. (Jan. 11, 2002) Going to Extremes. INFORMATIONWEEK [Online]. Available: www.informationweek.com/story/IWK20020111S0046 Copeland, L. (Oct. 17, 2001). Extreme programming moves slowly into the enterprise. COMPUTERWORLD [Online]. Available: www.computerworld.com/softwaretopics/software/story/0,10801,64850,00.html Copeland, L. (Dec. 03, 2001). Extreme programming. COMPUTERWORLD [Online]. Available: www.computerworld.com/softwaretopics/software/appdev/story/0,10801,66192,00.html Copeland, L. (Oct. 02, 2001). An Extreme Move by Capital One. COMPUTERWORLD [Online]. Available: www.computerworld.com/softwaretopics/software/appdev/story/0,10801,64927,00.html Kay, R. (May 14, 2002). System Development Life Cycle. COMPUTERWORLD [Online]. Available: www.computerworld.com/developmenttopics/development/story/0,10801,71151,00.html Shahzad Malik and Jose Ruben Palencia. (December 6,1999) Synchronize and Stabilize VS. Open-Source. Francis Bordeleau, Carleton University, Ottawa, Ontario, Canada Microsoft Solutions Framework White Paper (December 10,1999) Microsoft Corporation, pp. 2131 Landy, James (Jan. 26, 2001) Lecture: Applied Software Management, University of Ca., Berkeley. [Online]. Available: http://bmrc.berkeley.edu/courseware/ba293/spring01/lectures/process/sld013.htm