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©Ian Sommerville 2000 Software Engineering, 6th edition. Chapter 4 Slide 1
Project management
l Organising, planning andscheduling software projects
©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
©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
©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
©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
©Ian Sommerville 2000 Software Engineering, 6th edition. Chapter 4 Slide 6
Management activities
©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
©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
©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
©Ian Sommerville 2000 Software Engineering, 6th edition. Chapter 4 Slide 10
Project planning
©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
©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.
©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
©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
©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
©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
©Ian Sommerville 2000 Software Engineering, 6th edition. Chapter 4 Slide 17
Project scheduling
©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
©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
©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
©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
©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)
©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
©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
©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
©Ian Sommerville 2000 Software Engineering, 6th edition. Chapter 4 Slide 26
Risk management
©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
©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.
©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
©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
©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
©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.
©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
©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
©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
©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.
©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
©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
©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
©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