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Iterative Project Management

Iterative Project Management. Chapter 7.2 – Evolution and Phase Planning Modified considerably by your Instructor. Overview: Iterations Across The Lifecycle. Inception Executable release optional May only be one iteration Elaboration Demonstrate critical use cases

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Iterative Project Management

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  1. Iterative ProjectManagement Chapter 7.2 – Evolution and Phase Planning Modified considerably by your Instructor

  2. Overview: Iterations Across The Lifecycle • Inception • Executable release optional • May only be one iteration • Elaboration • Demonstrate critical use cases • Result in executable architecture • Construction • Result in usable software • Typically two or more iterations • Transition • Releases based on feedback and fixes • Early iterations address: • High risks • Stability • Understanding • Late iterations address: • Functionality • Performance • Robustness Iterative Project Management / 04 - Phase Planning and Assessment

  3. Planning an Evolution:Iteration Patterns – To show different Strategies… • Incremental Development • Evolutionary Development • Incremental Delivery • Extreme Programming / No Elaboration • Immediate Construction / Virtual Phases Iterative Project Management / 04 - Phase Planning and Assessment

  4. An Incremental Development Strategy (1 of 2) • This is the ‘ideal’ iteration pattern offering all the benefits of ‘rapid application development’ (RAD) without the risks. (Slide next page) • “The incremental strategy determines user needs and defines the system requirements, then performs rest of development in a sequence of builds. • The first build incorporates parts of the planned capabilities, the next build adds more capabilities, and so on until the system is complete.” [Software Development and Documentation, MIL-STD-498, U.S. Department of Defense, 12/1994] • The following iterations are characteristic: • a short Inception iteration to establish scope, vision; define business case • a single Elaboration iteration; requirements defined, architecture established • several Construction iterations; use cases realized, architecture fleshed-out • several Transition iterations, migrate product into the user community Iterative Project Management / 04 - Phase Planning and Assessment

  5. Resources Conceptual Prototype ArchitecturalBaseline Release Delivery Inception Elaboration Construction Transition Time Incremental Development - Strategy This strategy is appropriate when: • Problem domain is familiar. • Architecture is already proven / familiar • Risks well understood and under control • Team is experienced. • A RAD approach…. Iterative Project Management / 04 - Phase Planning and Assessment

  6. Evolutionary Development – Strategy (1 of 2) • This is the pattern that most team’s first iterative and incremental evolution conforms to. (Slide next page) • "The evolutionary strategy differs from the incremental in acknowledging user needs are not fully understood, and requirements cannot be defined up front, • Requirements are refined in each successive build." [MIL-STD-498] • The following iterations are characteristic: • Short Inception iteration - establish scope, vision; define business case • Several Elaboration iterations; requirements refined at each iteration and the architecture evolved • One or two Construction iterations; use cases realized, architecture is expanded upon; the application given a final polish • Several Transition iterations to migrate product into user community Iterative Project Management / 04 - Phase Planning and Assessment

  7. Resources Conceptual Prototype ArchitecturalBaseline Release Delivery Inception Elaboration Const’n Transition Time Evolutionary Development This strategy is appropriate when: • Problem domain - new or unfamiliar. • Architecture - new or unfamiliar all high risk • Iterative development - new or unfamiliar factors… • Team - inexperienced. • (note: number of iterations only for illustrative purposes) Iterative Project Management / 04 - Phase Planning and Assessment

  8. An Incremental Delivery Strategy…(1 of 2) • Pattern where multiple deliveries provided to customer is quite common for Internet site development where new content releases are expected monthly • May be required for tight time-to-market pressures, where delivery of certain key features early can yield significant business benefits. [Tom Gilb, Principles of Software Engineering Management, Wokingham, Addison-Wesley, 1988]. • In terms of the phase-iteration approach, the transition phase begins early on and has the most iterations. •  Strategy requires a verystablearchitecture, which is hard to achieve in an initial development cycle, for an "unprecedented" system. • The following iterations are characteristic: • Short Inception iteration: establish scope, vision: define business case • Single Elaboration iteration - a stable architecture is baselined • Single Construction iteration: use cases realized; architecturefleshed-out • Several Transitioniterations each of which delivers a new release of the product (with increased functionality) into the user community Iterative Project Management / 04 - Phase Planning and Assessment

  9. Resources Delivery Delivery Delivery Delivery Delivery Delivery Conceptual Prototype ArchitecturalBaseline Inception Elaboration Const’n Transition Time Incremental Delivery Strategy (2 of 2) This strategy is appropriate when: • Small increments have high value to the customer. • The architecture is already proven and familiar • The requirements are stable and low risk • The team is experienced in the architecture and the domain Iterative Project Management / 04 - Phase Planning and Assessment

  10. Immediate Construction / Virtual Phases (1` of 2) • In some cases, anchor point milestones can be merged. • A project deciding to use a mature and appropriately scalable 4th generation language (4GL) or product line framework will have already determined its choice of life cycle architecture by its LCO milestone enabling the LCO and LCA milestones to be merged. • As Barry Boehm observed, in his paper Spiral Development: Experience, Principles and Refinements (CMU/SEI-2000-SR-008), • Merging of the milestones is often compounded by the fact that anotherproject (typically a feasibility project or the previousrelease) has already done the work for you. • Leads to pattern appearing like no Inception or Elaboration • In this case the phases have been suppressed but the milestones are still there, with the reviewsbeingundertakenbefore the set of construction iterations can commence. Iterative Project Management / 04 - Phase Planning and Assessment

  11. Resources FirstRelease Delivery LCO and LCAPassed Construction Transition Time Immediate Construction / Virtual Phases (2 of 2) This strategy is appropriate when: • Architecture already proven and familiar • Requirements are known and of low technical risk • Team is experienced in the architecture and the domain • Project is collaborative and informal Iterative Project Management / 04 - Phase Planning and Assessment

  12. No Elaboration Strategy • This is another variant where milestones have been merged providing impression of no Elaboration Phase. • Enter most ‘Extreme Programming’ and SCRUM projects Architecture is a given at the start of the set of development iterations. • Architecture can be adjusted by refactoring during Construction but this is typical of most iterative and incremental projects post LCA. • Some Extreme Programming authors, most noticeably Martin Fowler, would allow technical concerns to affect the allocation of work to the initial development iterations creating an informal Elaboration Phase. Iterative Project Management / 04 - Phase Planning and Assessment

  13. Agile’s Terminology – via Kent Beck • Note In Agile and Iterative Development a Manager’s Guide, the XP Lifecycle phases as defined by Beck are described as: • Exploration - Purpose: Enough well-estimated story cards for first release, feasibility ensured. • Activities: Prototypes, exploratory proof of technology programming, story card writing and estimating • Planning - Purpose: Agree on date and stories for first release. • Activities: Release Planning Game, story card writing and estimating • Iterations To First Release - Purpose: Implement a tested system ready for release. • Activities: testing, programming, Iteration Planning Game, task writing, estimating • Productionizing - Purpose: Operational deployment. • Activities: documentation, training. marketing …. • Maintenance - Purpose: Enhance, fix, build major releases. • Activities: May include these phases again for incremental releases • These have been mapped to the UP phases for the purpose of this example Iterative Project Management / 04 - Phase Planning and Assessment

  14. Resources Start Development Iterations / First Release Date Agreed Release Delivery Inception Construction Transition Time No Elaboration This strategy is appropriate when: • Architecture is already proven and familiar • Requirements are known and of low technical risk • Team is experienced in the architecture and the domain • Project team is small; project is collaborative and informal Iterative Project Management / 04 - Phase Planning and Assessment

  15. Resources Conceptual Prototype ArchitecturalBaseline Release Delivery Resources FirstRelease Delivery LCO and LCAPassed Time Inception Elaboration Const’n Transition Time Construction Transition Resources Delivery Delivery Delivery Delivery Delivery Delivery Conceptual Prototype ArchitecturalBaseline Conceptual Prototype ArchitecturalBaseline Release Delivery Inception Elaboration Const’n Transition Inception Elaboration Construction Transition Time Time Typical Iteration Patterns for Multiple Release In practice you often end up with a hybrid, some evolution at the beginning, some incremental building, and multiple deliveries. Immediate Construction (2) Evolutionary (1) Incremental delivery (4) Incremental (3) Resources Iterative Project Management / 04 - Phase Planning and Assessment

  16. Think: • Among the advantages of the Unified Process phased iterative model is that it lets you accommodate a hybrid approach, simply by increasing the length and number of iterations in particular phases: • For complex or unfamiliar problem domains, where there is a high degree of exploratory business work required: increase the length of, and the number of iterations in, the inception phase. • For complex or unfamiliar technology problems, where there is a high degree of technological exploratory work required: increase the length of, and the number of iterations in, the elaboration phase. • For more complex development technologies, where there is complexity translating the requirements and design into code: increase the length of, and the number of iterations in, the construction phase. • To deliver software in a series of frequent incremental releases: increase the length of, and the number of iterations in, the transition phase. Iterative Project Management / 04 - Phase Planning and Assessment

  17. How To Use The Iteration Patterns • Think about your risks • Think about your team’s skills and experience • Think about where your project is in the lifecycle • Select a pattern as a reference model • Don’t be scared to adjust the model • You may require a hybrid pattern Iterative Project Management / 04 - Phase Planning and Assessment

  18. How To Use The Numbers • Use the numbers to challenge your plans and estimates • The numbers are for “typical projects” • You should be able to explain why your project doesn’t conform • The numbers for Inception and Transition carry least weight: • These can vary massively depending on the nature of the project • These figures are not part of the COCOMO statistical model • Elaboration should be small in comparison to Construction when consideredacross the entire endeavor • Architecture is the most important 20% of the development • Elaboration may be relatively large in early project evolutions The only thing we know for certain about yourproject is that it is not typical Iterative Project Management / 04 - Phase Planning and Assessment

  19. Some Hints and Tips • Name Iterations – they have a theme • Number iterations within phases. • Makemilestones real to the business • Give project a heartbeat • Be prepared to adjust iteration numbers and lengths based on lessons learned • Anything beyond the next iteration is only a sketch •  You cannot create a concrete plan until the end of Elaboration – there are too many unknowns Iterative Project Management / 04 - Phase Planning and Assessment

  20. Effort By Phase By Discipline Note: COCOMO II uses Design instead of Analysis and Design. Analysis is not mentioned in the breakdown. Iterative Project Management / 04 - Phase Planning and Assessment

  21. What Gets Produced? The Key Development Products Iterative Project Management / 04 - Phase Planning and Assessment

  22. The 10 Essentials of RUP • Vision – Develop a Vision • Plan – Manage to the Plan • Risks – Identify and Mitigate Risks • Issues – Assign and Track Issues • Business Case – Examine the Business Case • Architecture – Design a Component Architecture • Product – Incrementally Build and Test the Product • Evaluation – Regularly Assess Results • Change Requests – Manage and Control Change • User Support – Provide Assistance to the User Source: The Ten Essentials of RUP – The Essence of an Effective Development Process, Leslee Probasco, Rational Software White Paper Iterative Project Management / 04 - Phase Planning and Assessment

  23. Phase Review • What to look for at a Phase Review • Why • What • When • Who • Where • How • How Much The Phase Reviews are stakeholder decision points.A go / no go decision is made based upon the business case, risks, progress and plans. Iterative Project Management / 04 - Phase Planning and Assessment

  24. Phases and Use Cases By the end of: * A small percentage may be addressed for proof of concept purposes. Source: Adapted from The Unified Software Development Process, Jacobson et al (page 358). Iterative Project Management / 04 - Phase Planning and Assessment

  25. Summary / Conclusion • Each Phase is driven by a different set of forces • Inception – Business risks • Elaboration – Technical risks • Construction – Project logistical risks • Transition – Solution roll-out risks • Each phase needs to be managed a little differently • Each phased requires a different mixture of skills and levels of resources; it is not unreasonable to expect that different teams may staff each phase so long as there is a continuity of vision and expertise across phases • Be rigorous about phase-end milestones • Do not move to next phase until you have met milestone objectives • Don’t be pressured by the schedule into “declaring victory” – you will pay for it later! Iterative Project Management / 04 - Phase Planning and Assessment

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