Planning and Managing a Software

concretecakeΠολεοδομικά Έργα

29 Νοε 2013 (πριν από 3 χρόνια και 11 μήνες)

74 εμφανίσεις

CSE 7315
-

SW Project Management / Module 10
-

WBS Construction

Copyright © 1995
-
2006, Dennis J. Frailey, All Rights Reserved

CSE7315M10

Slide
1

August 12, 2006

SMU CSE 7315

Planning and Managing a Software
Project



Module 10

Constructing the Work Breakdown
Structure

CSE7315M10

Slide #
2

August 12, 2006

CSE 7315
-

SW Project Management / Module 10
-

WBS Construction

Copyright © 1995
-
2006, Dennis J. Frailey, All Rights Reserved

Objectives of This Module


To discuss the process of
constructing a work breakdown
structure


To discuss other issues related to the
work breakdown structure

Text, chapter 6

CSE7315M10

Slide #
3

August 12, 2006

CSE 7315
-

SW Project Management / Module 10
-

WBS Construction

Copyright © 1995
-
2006, Dennis J. Frailey, All Rights Reserved

Use of a WBS in Detailed Planning

(high level view)

1) Construct (or refine) the WBS

2) Trace the WBS to the source
documents

3) Perform (or update) cost and
schedule estimates

… continued

CSE7315M10

Slide #
4

August 12, 2006

CSE 7315
-

SW Project Management / Module 10
-

WBS Construction

Copyright © 1995
-
2006, Dennis J. Frailey, All Rights Reserved

Use of a WBS in Detailed Planning

(high level view)

(continued)

4) Determine if WBS is consistent
with size, cost and schedule
estimates

5) Identify Risks

6) Repeat as necessary


To correct discrepancies


To refine during re
-
planning

CSE7315M10

Slide #
5

August 12, 2006

CSE 7315
-

SW Project Management / Module 10
-

WBS Construction

Copyright © 1995
-
2006, Dennis J. Frailey, All Rights Reserved

Steps for Constructing a WBS

1. The
software hunt

-

identify SW tasks

2. Place software within the
project WBS

3. Determine the
architecture

of the
software portion(s) of the WBS

4.
Populate

the chosen WBS structure with
tasks from source documents

5. Develop WBS to source documents
trace
matrix


6. Determine the
cost category

for each
activity

CSE7315M10

Slide #
6

August 12, 2006

CSE 7315
-

SW Project Management / Module 10
-

WBS Construction

Copyright © 1995
-
2006, Dennis J. Frailey, All Rights Reserved

1. The Software Hunt

Go through the source documents and
make a complete list of all items that
impact the cost of doing the software

Document

Paragraph


Description

SOW


1.3.4



Design Software for Compiler

SOW


2.3.3



Travel for Design Reviews

...

Contract

7.13.2.a




Follow ISO Standard 5432f

Rqmts. Doc.

3.4



Use data compression

...

Customer

Meeting on 3/5/05 Code all software in Java +++

CSE7315M10

Slide #
7

August 12, 2006

CSE 7315
-

SW Project Management / Module 10
-

WBS Construction

Copyright © 1995
-
2006, Dennis J. Frailey, All Rights Reserved

Source Documents

Don’t forget that there are many possible
source documents

SOW (usually the best item to start with)

Specifications

Concept of operation documents

Requirements documents of many kinds

Design documents

Standards (internal and external)

Customer conversations

Test criteria or expectations

CSE7315M10

Slide #
8

August 12, 2006

CSE 7315
-

SW Project Management / Module 10
-

WBS Construction

Copyright © 1995
-
2006, Dennis J. Frailey, All Rights Reserved

2. Place Software Within the

Project WBS


Many organizations have a standard
WBS architecture for projects


If not, then determine what project
requirements may be applicable


For example, your project manager may
have a specific approach
--

number of
levels, where to show certain kinds of
costs, etc.


Know the risks of your approach

CSE7315M10

Slide #
9

August 12, 2006

CSE 7315
-

SW Project Management / Module 10
-

WBS Construction

Copyright © 1995
-
2006, Dennis J. Frailey, All Rights Reserved

Sample Project WBS with
Software Embedded in Hardware

Radar

Sig. Proc.

Antenna

Power S.

Cabinet

Computer

Software

Analog

This approach can result in a large number of
software elements in the WBS. A spreadsheet or
data base may be handy for tracking them all.

CSE7315M10

Slide #
10

August 12, 2006

CSE 7315
-

SW Project Management / Module 10
-

WBS Construction

Copyright © 1995
-
2006, Dennis J. Frailey, All Rights Reserved

Sample Project WBS with

Software Independent of Hardware

This approach may tend to isolate software planning
from the rest of the system, resulting in inconsistent
interpretations of requirements, etc.

System

Software

Electrical

Mechanical

Management

Editor

etc.

Compiler

CSE7315M10

Slide #
11

August 12, 2006

CSE 7315
-

SW Project Management / Module 10
-

WBS Construction

Copyright © 1995
-
2006, Dennis J. Frailey, All Rights Reserved

3. Determine the Architecture


of the Software WBS


Many organizations have standard
software WBS architectures to
help keep track of costs
consistently across the organization



Different software items may need
different WBS structures


See a later slide for some of the advantages of
a standard WBS architecture

CSE7315M10

Slide #
12

August 12, 2006

CSE 7315
-

SW Project Management / Module 10
-

WBS Construction

Copyright © 1995
-
2006, Dennis J. Frailey, All Rights Reserved

Some Sample Software WBSs

Software

Word

Proc.

Data

base

Spread

sheet

User

I/f

Editor

For
-

matter

Rqmts

Design

Code

Test

Software

Word

Proc.

Data

base

Spread

sheet

User

I/f

Editor

For
-

matter

Rqmts

Design

Code

Test

CSE7315M10

Slide #
13

August 12, 2006

CSE 7315
-

SW Project Management / Module 10
-

WBS Construction

Copyright © 1995
-
2006, Dennis J. Frailey, All Rights Reserved

Sample WBS Architectures

All Software


Products


Components



Process Steps

All Software


Process Steps


Products



Components

All Software


Organizations


Products





. . .

All Software


Products


Organizations





. . .

CSE7315M10

Slide #
14

August 12, 2006

CSE 7315
-

SW Project Management / Module 10
-

WBS Construction

Copyright © 1995
-
2006, Dennis J. Frailey, All Rights Reserved

4. Populate the WBS


Assign each activity identified in step
1 to an appropriate place in the work
breakdown structure

SOW 1.1.1

Develop C Compiler


1.0 Software for “C” Compiler

SPEC 2.0

Develop Compiler


1.1 Build a “C” Compiler

SPEC 2.1

User I/F for PC



1.1.1 Build a User Interface

PROC STD 3.4

Requirements Analysis 1.1.1.1 RA for User I/F

PROC STD 3.5

Design




1.1.1.2 Design for User I/F


.....



.....




.....

SPEC 2.2

File System



1.1.2 Build a File System


....



....




....

SPEC 3.0

Test IAW Company Stds 1.2

Build the Test Suite


....



....




....

SOW 2.3.4

Provide User Guide


1.3 Write Documentation


....



....




....

CSE7315M10

Slide #
15

August 12, 2006

CSE 7315
-

SW Project Management / Module 10
-

WBS Construction

Copyright © 1995
-
2006, Dennis J. Frailey, All Rights Reserved

Document

Parag


WBS#

Description

SOW


1.3.4


1.1.2.2 Design Software for Compiler

SOW


2.3.3


1.7.1


Travel for Design Reviews

Requirements

Specifications 3.1.1


1.1.2.4 Perform Quality Audit

5. Construct a Trace Matrix from
the WBS to the Source Documents


Add a WBS activity number column to
the list constructed in step 1.

CSE7315M10

Slide #
16

August 12, 2006

CSE 7315
-

SW Project Management / Module 10
-

WBS Construction

Copyright © 1995
-
2006, Dennis J. Frailey, All Rights Reserved

Additional (Optional)
Information in WBS Trace


Who is responsible for estimating cost


Who is responsible for development


What paragraph of the software
development plan addresses this task


What standards are to be applied in
performing this task


What is the final cost estimate for
this WBS item


Filled in after estimating cost

CSE7315M10

Slide #
17

August 12, 2006

CSE 7315
-

SW Project Management / Module 10
-

WBS Construction

Copyright © 1995
-
2006, Dennis J. Frailey, All Rights Reserved

Using the WBS Trace Matrix

1) Sort by source document & paragraph
and make sure each task is covered in
the WBS

2) Sort by WBS number and make sure
each corresponds to a legitimate
activity that must be performed

3) Sort by WBS and requirements
document to identify all the
requirements that must be met by
each activity (helps in cost estimating)

CSE7315M10

Slide #
18

August 12, 2006

CSE 7315
-

SW Project Management / Module 10
-

WBS Construction

Copyright © 1995
-
2006, Dennis J. Frailey, All Rights Reserved

Use of the Trace Matrix During
Project Execution


When requirements are changed, you
can determine which activities are
potentially affected


When activities encounter problems,
you can determine which
requirements or contract stipulations
may need to be renegotiated


CSE7315M10

Slide #
19

August 12, 2006

CSE 7315
-

SW Project Management / Module 10
-

WBS Construction

Copyright © 1995
-
2006, Dennis J. Frailey, All Rights Reserved

Doc

Parag

WBS#

Description

SOW

1.3.4


1.1.2.2

Design Software for Compiler

SOW

1.3.4


1.1.3.2

Design Software for Editor

SOW

2.3.4


1.1.3.2

Use Booch Design Method

SOW

2.3.3


1.7.1

Travel for Design Reviews

Suppose SOW 1.3.4 says "design software"

and SOW 2.3.4 says "use Booch design method"

Redundancy OK in the

Trace Matrix

CSE7315M10

Slide #
20

August 12, 2006

CSE 7315
-

SW Project Management / Module 10
-

WBS Construction

Copyright © 1995
-
2006, Dennis J. Frailey, All Rights Reserved

Document

Parag

WBS#

Description


Category

SOW


1.3.4 1.1.2.2

Design Software





for Compiler




S

. . .


. . .


. . .

. . .

SOW


2.3.3 1.7.1

Travel for Design





Reviews




C

. . .

Continued...

6. Determine Cost Categories


Determine the cost category for each
activity in the WBS (step 4).


Document in the trace matrix (step 5)

CSE7315M10

Slide #
21

August 12, 2006

CSE 7315
-

SW Project Management / Module 10
-

WBS Construction

Copyright © 1995
-
2006, Dennis J. Frailey, All Rights Reserved

Typical Cost Categories

Code
Category
Affects
Examples
S
Software
Development
Cost &
Schedule
Software Design, Software
Coding, Software Testing
SA
Additional
Software
Effort
Cost &
Schedule
Software Requirements,
System Testing
P
Software
Support
Cost
Software Management, SQA,
Configuration Management
AL
Additional
Labor
Cost
Special Audits,
Document Generation
AD
Additional
Dollars
Cost
Travel, Development Tools,
Special Equipment,
CSE7315M10

Slide #
22

August 12, 2006

CSE 7315
-

SW Project Management / Module 10
-

WBS Construction

Copyright © 1995
-
2006, Dennis J. Frailey, All Rights Reserved

Notes

See
assignment 2

for more
information about the format of a
typical work breakdown structure


If the cost category step is not
done here, it needs to be done
later, during the cost estimating
process

CSE7315M10

Slide #
23

August 12, 2006

CSE 7315
-

SW Project Management / Module 10
-

WBS Construction

Copyright © 1995
-
2006, Dennis J. Frailey, All Rights Reserved

Notes

(continued)


There will be some items from step 1 that
are scattered throughout many WBS
elements (example: use a particular
standard or programming language)


Costs directly caused by using that standard
or language can be isolated to a separate
WBS element


For example, the costs of purchasing a
compiler or carrying out a mandated review
or producing a document that would not
otherwise be needed

CSE7315M10

Slide #
24

August 12, 2006

CSE 7315
-

SW Project Management / Module 10
-

WBS Construction

Copyright © 1995
-
2006, Dennis J. Frailey, All Rights Reserved

Notes

(continued)


There may be some items from step 1
that do not seem to fit the standard
WBS architecture


Examples: warranty costs, special testing, ...


You usually just add another activity
somewhere in the WBS


You may need to be creative

CSE7315M10

Slide #
25

August 12, 2006

CSE 7315
-

SW Project Management / Module 10
-

WBS Construction

Copyright © 1995
-
2006, Dennis J. Frailey, All Rights Reserved

Notes

(continued)


Some items in the organization’s
standard WBS may not be explicitly
stated in source documents


Examples: training, management, facilities,
development tools


For these you determine whether they
are needed and, if so, get agreement
with your customer or system engineer
and refer to the relevant company
policies or standards in your trace

CSE7315M10

Slide #
26

August 12, 2006

CSE 7315
-

SW Project Management / Module 10
-

WBS Construction

Copyright © 1995
-
2006, Dennis J. Frailey, All Rights Reserved

Notes

(continued)


The standard WBS acts as a reminder
not to forget things like these.



You can use the standard WBS like a
checklist


You don’t want to overlook anything that
will cost you money or time or effort


Often, many activities are assumed without
explicit mention in source documents

CSE 7315
-

SW Project Management / Module 10
-

WBS Construction

Copyright © 1995
-
2006, Dennis J. Frailey, All Rights Reserved

CSE7315M10

Slide
27

August 12, 2006

WBS Issues

Practical Issues that Often
Come Up when Developing a
WBS

CSE7315M10

Slide #
28

August 12, 2006

CSE 7315
-

SW Project Management / Module 10
-

WBS Construction

Copyright © 1995
-
2006, Dennis J. Frailey, All Rights Reserved

(WBS Issues)

Customer Imposed Format

Issue
:


Customer requires that the design
document should be written in a
specific format that your process does
not require


It will cost you extra money and time to
do this


You will need to learn how to use the
customer’s desired format

CSE7315M10

Slide #
29

August 12, 2006

CSE 7315
-

SW Project Management / Module 10
-

WBS Construction

Copyright © 1995
-
2006, Dennis J. Frailey, All Rights Reserved

Resolution

Option A:



Include the incremental cost of producing
this format as a separate WBS item


This shows the customer what it costs


Be prepared to reduce the cost accordingly if
the customer says “OK, use your own format.”

Option B:



Add the cost into the basic cost of
software development


Will make your productivity rate slightly lower

CSE7315M10

Slide #
30

August 12, 2006

CSE 7315
-

SW Project Management / Module 10
-

WBS Construction

Copyright © 1995
-
2006, Dennis J. Frailey, All Rights Reserved

(WBS Issues)

Representing the Cost of
Support Tasks

Issue (example):



Configuration management (CM) is a
significant overall cost, but a minor
increment to individual component cost
estimates


How do you represent it in the WBS?

CSE7315M10

Slide #
31

August 12, 2006

CSE 7315
-

SW Project Management / Module 10
-

WBS Construction

Copyright © 1995
-
2006, Dennis J. Frailey, All Rights Reserved

Resolution of Support Cost Issue

Option A:


Include a CM task for each software
component or product


Tends to create a lot of small work packages

Option B:



Include all CM cost as a separate item at a
higher WBS level.


Tends to obscure the details of what it costs,
and makes the total look large and consequently
invites arbitrary cuts in CM cost

CSE7315M10

Slide #
32

August 12, 2006

CSE 7315
-

SW Project Management / Module 10
-

WBS Construction

Copyright © 1995
-
2006, Dennis J. Frailey, All Rights Reserved

(WBS Issues)

Organizational Standard Not
Being Followed

Issue:



Customer or program manager requires a
WBS format or architecture that does not
conform with organizational standard


You may be called on the carpet for
violating that standard


If you don’t use the standard, you may lose
some of the benefits, such as support,
assistance, or data for comparison with
similar programs in the past

CSE7315M10

Slide #
33

August 12, 2006

CSE 7315
-

SW Project Management / Module 10
-

WBS Construction

Copyright © 1995
-
2006, Dennis J. Frailey, All Rights Reserved

Resolution

Option A:



Use a spreadsheet or data base program
to sort the WBS into either format

Option B:


Negotiate to see if they will accept the
standard format

Option C:


Retain documentation of “non
-
standard”
requirement and trace your format to the
standard format

CSE7315M10

Slide #
34

August 12, 2006

CSE 7315
-

SW Project Management / Module 10
-

WBS Construction

Copyright © 1995
-
2006, Dennis J. Frailey, All Rights Reserved

Risks in Preparing a WBS

CSE7315M10

Slide #
35

August 12, 2006

CSE 7315
-

SW Project Management / Module 10
-

WBS Construction

Copyright © 1995
-
2006, Dennis J. Frailey, All Rights Reserved

Risks
-

I

Too Much Detail


Increases overhead of monitoring and
estimation


Customers or managers might insist
on tracking based on the WBS


You may have two WBSs to get
around this: a “formal” WBS at the
high level and a “working” WBS at the
detail level

CSE7315M10

Slide #
36

August 12, 2006

CSE 7315
-

SW Project Management / Module 10
-

WBS Construction

Copyright © 1995
-
2006, Dennis J. Frailey, All Rights Reserved

Risks
-

II

Work Packages are Vague


Look for concrete starting & ending
events with specific evaluation
criteria


A work package should be discrete,
trackable, & measurable


CSE7315M10

Slide #
37

August 12, 2006

CSE 7315
-

SW Project Management / Module 10
-

WBS Construction

Copyright © 1995
-
2006, Dennis J. Frailey, All Rights Reserved

Risks
-

III

Excluding Certain Tasks


Make sure everything is covered


It is easy to assume someone else
covered it


If you don’t know, ask


Exclusion implies 0 cost, which is
rarely true if you must do the task

CSE7315M10

Slide #
38

August 12, 2006

CSE 7315
-

SW Project Management / Module 10
-

WBS Construction

Copyright © 1995
-
2006, Dennis J. Frailey, All Rights Reserved

Risks
-
IV

Duplication of Activities



It is easy to have the same work
show up in more than one place,
especially on a large project



Managers must “scrub” the WBS

CSE7315M10

Slide #
39

August 12, 2006

CSE 7315
-

SW Project Management / Module 10
-

WBS Construction

Copyright © 1995
-
2006, Dennis J. Frailey, All Rights Reserved

Risk Mitigation Approaches


WBS inspection or walkthrough


Look for completeness, consistency, well
defined activities, etc.


Let others see the WBS (you tend to have
tunnel vision and may miss something)


Trace to source documents (and, later, to
cost estimate)


Remember that the WBS is part of the
plan


Include WBS revisions in replanning activities

CSE 7315
-

SW Project Management / Module 10
-

WBS Construction

Copyright © 1995
-
2006, Dennis J. Frailey, All Rights Reserved

CSE7315M10

Slide
40

August 12, 2006

Goals and Observations

CSE7315M10

Slide #
41

August 12, 2006

CSE 7315
-

SW Project Management / Module 10
-

WBS Construction

Copyright © 1995
-
2006, Dennis J. Frailey, All Rights Reserved

Goals of a Good WBS
(1)

1) Specify the ingredients of the project
clearly and concisely

2) Identify the responsibilities of each
task and its place within the whole

3) Identify project performance targets
at every level

(1) Maciariello, Joseph A., “Making program management work,”
Tutorial on
Software Management
, IEEE Computer Society Press, 1986, p. 93.

CSE7315M10

Slide #
42

August 12, 2006

CSE 7315
-

SW Project Management / Module 10
-

WBS Construction

Copyright © 1995
-
2006, Dennis J. Frailey, All Rights Reserved

Goals of a Good WBS

(continued)

4) Support the comparison of actual
performance with target values

5) Motivate people to meet targets

6) [Others that you might include]

Part of an organizational standard WBS should be a
set of agreed
-
upon goals for the WBS, so that all
WBS efforts are geared toward those goals.

CSE7315M10

Slide #
43

August 12, 2006

CSE 7315
-

SW Project Management / Module 10
-

WBS Construction

Copyright © 1995
-
2006, Dennis J. Frailey, All Rights Reserved

Observations on the WBS


Different parts of the WBS could have
different levels of detail


Later updates of the WBS could provide
more detail than what is developed
initially

CSE7315M10

Slide #
44

August 12, 2006

CSE 7315
-

SW Project Management / Module 10
-

WBS Construction

Copyright © 1995
-
2006, Dennis J. Frailey, All Rights Reserved

Observations on the WBS
(continued)


Avoid making too many very small
work packages


If several of them have nearly identical
descriptions, see if you can combine
them.


Each level in the WBS multiplies by 5
-
10
the amount of detail that must be
estimated, tracked, etc.)


Trace the WBS to the requirements

CSE7315M10

Slide #
45

August 12, 2006

CSE 7315
-

SW Project Management / Module 10
-

WBS Construction

Copyright © 1995
-
2006, Dennis J. Frailey, All Rights Reserved

Module Summary


We showed a six
-
step method for
constructing a WBS


In practice, there are many issues
that call for judgment in creating an
effective WBS


There are many risks and issues
associated with developing a WBS

CSE7315M10

Slide #
46

August 12, 2006

CSE 7315
-

SW Project Management / Module 10
-

WBS Construction

Copyright © 1995
-
2006, Dennis J. Frailey, All Rights Reserved

References


Work Breakdown Structure

1. Maciariello, Joseph A., “Making


program management work,”
Tutorial
on Software Management
, IEEE
Computer Society Press, 1986, p. 93.

2. Tausworthe, Robert C., “The Work


Breakdown structure in Software


Project Management”,
Proceedings


of the Second Software Lifecycle


Management Workshop

CSE7315M10

Slide #
47

August 12, 2006

CSE 7315
-

SW Project Management / Module 10
-

WBS Construction

Copyright © 1995
-
2006, Dennis J. Frailey, All Rights Reserved

END OF

MODULE 10