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©Ian Sommerville 2000 Software Engineering, 6th edition. Chapter 4 Slide 1 Project management l Organising, planning and scheduling software projects

Project management

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Page 1: Project management

©Ian Sommerville 2000 Software Engineering, 6th edition. Chapter 4 Slide 1

Project management

l Organising, planning andscheduling software projects

Page 2: Project management

©Ian Sommerville 2000 Software Engineering, 6th edition. Chapter 4 Slide 2

Objectives

l To introduce software project management and todescribe its distinctive characteristics

l To discuss project planning and the planningprocess

l To show how graphical schedule representationsare used by project management

l To discuss the notion of risks and the riskmanagement process

Page 3: Project management

©Ian Sommerville 2000 Software Engineering, 6th edition. Chapter 4 Slide 3

Topics covered

l Management activities

l Project planning

l Project scheduling

l Risk management

Page 4: Project management

©Ian Sommerville 2000 Software Engineering, 6th edition. Chapter 4 Slide 4

l Concerned with activities involved in ensuringthat software is delivered on time and onschedule and in accordance with therequirements of the organisations developingand procuring the software

l Project management is needed because softwaredevelopment is always subject to budget andschedule constraints that are set by theorganisation developing the software

Software project management

Page 5: Project management

©Ian Sommerville 2000 Software Engineering, 6th edition. Chapter 4 Slide 5

l The product is intangible

l The product is uniquely flexible

l Software engineering is not recognized as anengineering discipline with the sane status asmechanical, electrical engineering, etc.

l The software development process is notstandardised

l Many software projects are 'one-off' projects

Software management distinctions

Page 6: Project management

©Ian Sommerville 2000 Software Engineering, 6th edition. Chapter 4 Slide 6

Management activities

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©Ian Sommerville 2000 Software Engineering, 6th edition. Chapter 4 Slide 7

l Proposal writing

l Project planning and scheduling

l Project costing

l Project monitoring and reviews

l Personnel selection and evaluation

l Report writing and presentations

Management activities

Page 8: Project management

©Ian Sommerville 2000 Software Engineering, 6th edition. Chapter 4 Slide 8

l These activities are not peculiar to softwaremanagement

l Many techniques of engineering projectmanagement are equally applicable to softwareproject management

l Technically complex engineering systems tendto suffer from the same problems as softwaresystems

Management commonalities

Page 9: Project management

©Ian Sommerville 2000 Software Engineering, 6th edition. Chapter 4 Slide 9

Project staffing

l May not be possible to appoint the ideal people towork on a project• Project budget may not allow for the use of highly-paid staff

• Staff with the appropriate experience may not be available

• An organisation may wish to develop employee skills on asoftware project

l Managers have to work within these constraintsespecially when (as is currently the case) there isan international shortage of skilled IT staff

Page 10: Project management

©Ian Sommerville 2000 Software Engineering, 6th edition. Chapter 4 Slide 10

Project planning

Page 11: Project management

©Ian Sommerville 2000 Software Engineering, 6th edition. Chapter 4 Slide 11

Project planning

l Probably the most time-consuming projectmanagement activity

l Continuous activity from initial concept throughto system delivery. Plans must be regularlyrevised as new information becomes available

l Various different types of plan may be developedto support the main software project plan that isconcerned with schedule and budget

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©Ian Sommerville 2000 Software Engineering, 6th edition. Chapter 4 Slide 12

Types of project plan

Plan DescriptionQuality plan Describes the quality procedures and

standards that will be used in a project.Validation plan Describes the approach, resources and

schedule used for system validation. Configurationmanagement plan

Describes the configuration managementprocedures and structures to be used.

Maintenance plan Predicts the maintenance requirements ofthe system, maintenance costs and effortrequired.

Staff development plan. Describes how the skills and experience ofthe project team members will bedeveloped.

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©Ian Sommerville 2000 Software Engineering, 6th edition. Chapter 4 Slide 13

Project planning process

Establish the project constraints Make initial assessments of the project parameters Define project milestones and deliverableswhile project has not been completed or cancelled loop

Draw up project scheduleInitiate activities according to schedule

Wait ( for a while ) Review project progress Revise estimates of project parameters Update the project schedule Re-negotiate project constraints and deliverables if ( problems arise ) then Initiate technical review and possible revision end ifend loop

Page 14: Project management

©Ian Sommerville 2000 Software Engineering, 6th edition. Chapter 4 Slide 14

Project plan structure

l Introduction

l Project organisation

l Risk analysis

l Hardware and software resource requirements

l Work breakdown

l Project schedule

l Monitoring and reporting mechanisms

Page 15: Project management

©Ian Sommerville 2000 Software Engineering, 6th edition. Chapter 4 Slide 15

Activity organization

l Activities in a project should be organised toproduce tangible outputs for management tojudge progress

l Milestones are the end-point of a process activity

l Deliverables are project results delivered tocustomers

l The waterfall process allows for thestraightforward definition of progress milestones

Page 16: Project management

©Ian Sommerville 2000 Software Engineering, 6th edition. Chapter 4 Slide 16

Milestones in the RE process

Evaluationreport

Prototypedevelopment

Requirementsdefinition

Requirementsanalysis

Feasibilityreport

Feasibilitystudy

Architecturaldesign

Designstudy

Requirementsspecification

Requirementsspecification

ACTIVITIES

MILESTONES

Page 17: Project management

©Ian Sommerville 2000 Software Engineering, 6th edition. Chapter 4 Slide 17

Project scheduling

Page 18: Project management

©Ian Sommerville 2000 Software Engineering, 6th edition. Chapter 4 Slide 18

Project scheduling

l Split project into tasks and estimate time andresources required to complete each task

l Organize tasks concurrently to make optimaluse of workforce

l Minimize task dependencies to avoid delayscaused by one task waiting for another tocomplete

l Dependent on project managers intuition andexperience

Page 19: Project management

©Ian Sommerville 2000 Software Engineering, 6th edition. Chapter 4 Slide 19

The project scheduling process

Estimate resourcesfor activities

Identify activitydependencies

Identifyactivities

Allocate peopleto activities

Create projectcharts

Softwarerequirements

Activity chartsand bar charts

Page 20: Project management

©Ian Sommerville 2000 Software Engineering, 6th edition. Chapter 4 Slide 20

Scheduling problems

l Estimating the difficulty of problems and hencethe cost of developing a solution is hard

l Productivity is not proportional to the number ofpeople working on a task

l Adding people to a late project makes it laterbecause of communication overheads

l The unexpected always happens. Always allowcontingency in planning

Page 21: Project management

©Ian Sommerville 2000 Software Engineering, 6th edition. Chapter 4 Slide 21

Bar charts and activity networks

l Graphical notations used to illustrate the projectschedule

l Show project breakdown into tasks. Tasks shouldnot be too small. They should take about a weekor two

l Activity charts show task dependencies and thethe critical path

l Bar charts show schedule against calendar time

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©Ian Sommerville 2000 Software Engineering, 6th edition. Chapter 4 Slide 22

Task durations and dependenciesTask Duration (days) DependenciesT1 8T2 15T3 15 T1 (M1)T4 10T5 10 T2, T4 (M2)T6 5 T1, T2 (M3)T7 20 T1 (M1)T8 25 T4 (M5)T9 15 T3, T6 (M4)T10 15 T5, T7 (M7)T11 7 T9 (M6)T12 10 T11 (M8)

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©Ian Sommerville 2000 Software Engineering, 6th edition. Chapter 4 Slide 23

Activity network

start

T2

M3T6

Finish

T10

M7T5

T7

M2T4

M5

T8

4/7/99

8 days

14/7/99 15 days

4/8/99

15 days

25/8/99

7 days

5/9/99

10 days

19/9/99

15 days

11/8/99

25 days

10 days

20 days

5 days25/7/99

15 days

25/7/99

18/7/99

10 days

T1

M1 T3T9

M6

T11

M8

T12

M4

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©Ian Sommerville 2000 Software Engineering, 6th edition. Chapter 4 Slide 24

Activity timeline4/7 11/7 18/7 25/7 1/8 8/8 15/8 22/8 29/8 5/9 12/9 19/9

T4

T1T2

M1

T7T3

M5T8

M3

M2T6

T5M4

T9

M7T10

M6

T11M8

T12

Start

Finish

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©Ian Sommerville 2000 Software Engineering, 6th edition. Chapter 4 Slide 25

Staff allocation4/7 11/7 18/7 25/ 1/8 8/8 15/8 22/8 29/8 5/9 12/9 19/9

T4

T8 T11

T12

T1

T3

T9

T2

T6 T10

T7

T5

Fred

Jane

Anne

Mary

Jim

Page 26: Project management

©Ian Sommerville 2000 Software Engineering, 6th edition. Chapter 4 Slide 26

Risk management

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©Ian Sommerville 2000 Software Engineering, 6th edition. Chapter 4 Slide 27

Risk management

l Risk management is concerned with identifyingrisks and drawing up plans to minimise theireffect on a project.

l A risk is a probability that some adversecircumstance will occur.• Project risks affect schedule or resources

• Product risks affect the quality or performance of the softwarebeing developed

• Business risks affect the organisation developing or procuringthe software

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©Ian Sommerville 2000 Software Engineering, 6th edition. Chapter 4 Slide 28

Software risksRisk Risk type DescriptionStaff turnover Project Experienced staff will leave the

project before it is finished.Management change Project There will be a change of

organisational management withdifferent priorities.

Hardware unavailability Project Hardware which is essential for theproject will not be delivered onschedule.

Requirements change Project andproduct

There will be a larger number ofchanges to the requirements thananticipated.

Specification delays Project andproduct

Specifications of essential interfacesare not available on schedule

Size underestimate Project andproduct

The size of the system has beenunderestimated.

CASE tool under-performance

Product CASE tools which support theproject do not perform as anticipated

Technology change Business The underlying technology on whichthe system is built is superseded bynew technology.

Product competition Business A competitive product is marketedbefore the system is completed.

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©Ian Sommerville 2000 Software Engineering, 6th edition. Chapter 4 Slide 29

The risk management process

l Risk identification• Identify project, product and business risks

l Risk analysis• Assess the likelihood and consequences of these risks

l Risk planning• Draw up plans to avoid or minimise the effects of the risk

l Risk monitoring• Monitor the risks throughout the project

Page 30: Project management

©Ian Sommerville 2000 Software Engineering, 6th edition. Chapter 4 Slide 30

The risk management process

Risk avoidanceand contingency

plans

Risk planning

Prioritised risklist

Risk analysis

List of potentialrisks

Riskidentification

Riskassessment

Riskmonitoring

Page 31: Project management

©Ian Sommerville 2000 Software Engineering, 6th edition. Chapter 4 Slide 31

Risk identification

l Technology risks

l People risks

l Organisational risks

l Requirements risks

l Estimation risks

Page 32: Project management

©Ian Sommerville 2000 Software Engineering, 6th edition. Chapter 4 Slide 32

Risks and risk typesRisk type Possible risksTechnology The database used in the system cannot process as many

transactions per second as expected.Software components which should be reused contain defectswhich limit their functionality.

People It is impossible to recruit staff with the skills required.Key staff are ill and unavailable at critical times.Required training for staff is not available.

Organisational The organisation is restructured so that different managementare responsible for the project.Organisational financial problems force reductions in the projectbudget.

Tools The code generated by CASE tools is inefficient.CASE tools cannot be integrated.

Requirements Changes to requirements which require major design rework areproposed.Customers fail to understand the impact of requirementschanges.

Estimation The time required to develop the software is underestimated.The rate of defect repair is underestimated.The size of the software is underestimated.

Page 33: Project management

©Ian Sommerville 2000 Software Engineering, 6th edition. Chapter 4 Slide 33

Risk analysis

l Assess probability and seriousness of each risk

l Probability may be very low, low, moderate, highor very high

l Risk effects might be catastrophic, serious,tolerable or insignificant

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©Ian Sommerville 2000 Software Engineering, 6th edition. Chapter 4 Slide 34

Risk analysisRisk Probability EffectsOrganisational financial problems force reductionsin the project budget.

Low Catastrophic

It is impossible to recruit staff with the skillsrequired for the project.

High Catastrophic

Key staff are ill at critical times in the project. Moderate SeriousSoftware components which should be reusedcontain defects which limit their functionality.

Moderate Serious

Changes to requirements which require majordesign rework are proposed.

Moderate Serious

The organisation is restructured so that differentmanagement are responsible for the project.

High Serious

The database used in the system cannot process asmany transactions per second as expected.

Moderate Serious

The time required to develop the software isunderestimated.

High Serious

CASE tools cannot be integrated. High TolerableCustomers fail to understand the impact ofrequirements changes.

Moderate Tolerable

Required training for staff is not available. Moderate TolerableThe rate of defect repair is underestimated. Moderate TolerableThe size of the software is underestimated. High TolerableThe code generated by CASE tools is inefficient. Moderate Insignificant

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©Ian Sommerville 2000 Software Engineering, 6th edition. Chapter 4 Slide 35

Risk planning

l Consider each risk and develop a strategy tomanage that risk

l Avoidance strategies• The probability that the risk will arise is reduced

l Minimisation strategies• The impact of the risk on the project or product will be reduced

l Contingency plans• If the risk arises, contingency plans are plans to deal with that

risk

Page 36: Project management

©Ian Sommerville 2000 Software Engineering, 6th edition. Chapter 4 Slide 36

Risk management strategiesRisk StrategyOrganisationalfinancial problems

Prepare a briefing document for senior management showinghow the project is making a very important contribution to thegoals of the business.

Recruitmentproblems

Alert customer of potential difficulties and the possibility ofdelays, investigate buying-in components.

Staff illness Reorganise team so that there is more overlap of work andpeople therefore understand each other’s jobs.

Defectivecomponents

Replace potentially defective components with bought-incomponents of known reliability.

Requirementschanges

Derive traceability information to assess requirements changeimpact, maximise information hiding in the design.

Organisationalrestructuring

Prepare a briefing document for senior management showinghow the project is making a very important contribution to thegoals of the business.

Databaseperformance

Investigate the possibility of buying a higher-performancedatabase.

Underestimateddevelopment time

Investigate buying in components, investigate use of a programgenerator.

Page 37: Project management

©Ian Sommerville 2000 Software Engineering, 6th edition. Chapter 4 Slide 37

Risk monitoring

l Assess each identified risks regularly to decidewhether or not it is becoming less or moreprobable

l Also assess whether the effects of the risk havechanged

l Each key risk should be discussed at managementprogress meetings

Page 38: Project management

©Ian Sommerville 2000 Software Engineering, 6th edition. Chapter 4 Slide 38

Risk factorsRisk type Potential indicatorsTechnology Late delivery of hardware or support software, many

reported technology problemsPeople Poor staff morale, poor relationships amongst team

member, job availabilityOrganisational organisational gossip, lack of action by senior

managementTools reluctance by team members to use tools, complaints

about CASE tools, demands for higher-poweredworkstations

Requirements many requirements change requests, customercomplaints

Estimation failure to meet agreed schedule, failure to clearreported defects

Page 39: Project management

©Ian Sommerville 2000 Software Engineering, 6th edition. Chapter 4 Slide 39

Key points

l Good project management is essential for projectsuccess

l The intangible nature of software causesproblems for management

l Managers have diverse roles but their mostsignificant activities are planning, estimating andscheduling

l Planning and estimating are iterative processeswhich continue throughout the course of aproject

Page 40: Project management

©Ian Sommerville 2000 Software Engineering, 6th edition. Chapter 4 Slide 40

l A project milestone is a predictable state wheresome formal report of progress is presented tomanagement.

l Risks may be project risks, product risks orbusiness risks

l Risk management is concerned with identifyingrisks which may affect the project and planning toensure that these risks do not develop into majorthreats

Key points