Software Project Planning IV

Software Engineering
Gagan Deep
Rozy Computech Services
3rd Gate, K.U., Kurukshetra
rozygag@yahoo.com

SOFTWARE CONFIGURATION MAMAGEMENT
 When we develop a software, the product (software)
undergoes many changes in their maintenance
phase, we need to handle these changes effectively.
 Several individual (programs) works together to
achieve this common goal. These individual
produces several work product (SC Items) e.g.
intermediate version of modules or test data used
during debugging, part of final product.
 The item that comprise all information produced as
part of the software process are collectively called a
software configuration.
Software Engineering by Gagan Deep
rozygag@yahoo.com 2

 As software development progresses, the number of
Software Configuration Items (SCI’s) increases rapidly.
 These are managed and controlled by SCM. This is where
we need software configuration management.
 A configuration of product refers not only to the product's
constituent, but also to specific version of the component.
 Therefore SCM is the discipline which
 Identify change
 Monitor and control change
 Ensure the proper implementation of change made to item.
 Auditing and reporting on the change made.
rozygag@yahoo.com 3

 Configuration management(CM) is an art of
identifying, organising and controlling
modifications to software being built by a
programming team.
 The goal is to maximize productivity by
minimizing mistakes(errors).
 CM is essential due to the inventory
management, library management and updation
management of the items important for the
project.
rozygag@yahoo.com 4

Importance of SCM
 It is useful in controlling and managing the access to
various SCIs e.g. by preventing the two member of a
team for checking out the same component for
modification at same time.
 It provide the tool to ensure that changes is being
properly implemented
 It has the capability of defining and storing the various
constituent of a software
 SCM is used in keeping a system in a consistent state
by automatically generating derived version upon
modification of same component.
rozygag@yahoo.com 5

SCM Process
 It uses the tools which ensure that the required change
has been properly implemented to the appropriate
component (item). Thus it answer to the following
questions
 How and when the change will be done to software?
 How to ensure the changes are done correctly?
 What procedure will be adopted to make the change?
 Who will be responsible for change ?
 How to rank/order for importance of various change or
items?
 How to manage the many version of the program?
rozygag@yahoo.com 6

 These questions lead us to the definition of five
SCM task:
 Identification
 Version Control
 Change Control,
 Configuration Auditing, and
 Status Reporting.
rozygag@yahoo.com 7

 Identification
○ Basic Object : Unit of Text created by a software
engineer during analysis, design, code, or test.
○ Aggregate Object : collection of basic objects and
other aggregate objects. Design Specification is an
aggregate object.
○ Each object has a set of distinct features that identify
it uniquely: a name, a description, a list of resources,
and a "realization".
○ The interrelationships between configuration objects
can be represented with a Module Interconnection
Language(MIL).
rozygag@yahoo.com 8

 Version Control
 Version Control combines procedures and tools to
manage different versions of configuration objects
that are created during the software process.
 Clemm describes version control in the context of
SCM: Configuration management allows a user to
specify alternative configurations of the software
system through the selection of appropriate versions.
This is supported by associating attributes with each
software version, and then allowing a configuration
to be specified [and constructed] by describing the
set of desired attributes.
rozygag@yahoo.com 9

 Change Control
 James Bach describes change control in context of
SCM is: Change control is vital. But the forces that
make it necessary also make it annoying.
 We worry about change because a small confusion in
the code can create a big failure in the product. But it
can also fix a big failure or enable wonderful new
capabilities.
 We worry about change because a single rogue
developer could sink the project; yet brilliant ideas
originate in the minds of those rogues, and
 A burdensome change control process could effectively
discourage them from doing creative work.
rozygag@yahoo.com 10

Bach recognizes that we face a balancing act.
 Too much change control and we create problems.
 Too little, and we create other problems.
 A Change request is submitted and evaluated to assess
technical merit, potential side effects, overall impact on
other configuration objects and system functions, and
projected cost of the change.
 The results of the evaluation are presented as a change
report, which is used by a change control
authority(CCA) - a person or group who makes a final
decision on the status and priority of the change.

 The "check-in" and "check-out" process
implements two important elements of change
control - access control and synchronization
control.
 Access control governs which software engineers
have the authority to access and modify a
particular configuration object.
 Synchronization control helps to ensure that
parallel changes, performed by two different
people, don't overwrite one another.
 The CCA may be composed of one person - the
project manager - or a number of people (e.g.,
representatives from software, hardware, database
engineering, support, marketing).

The role of the CCA is to take a global view, that
is, to assess the impact of change beyond the SCI
in question.
 How will the change affect hardware?
 How will the change affect performance?
 How will the change modify customer's
perception of the product?
 How will the change affect product quality and
reliability?
 These and many other questions are addressed
by the CCA.

 Configuration Auditing
 How can we ensure that the change has been properly
implemented? The answer is two fold:
 Formal technical reviews and
 The software configuration audit.
 The Formal Technical Review focuses on the technical
correctness of the configuration object that has been
modified. The reviewers assess the SCI to determine
consistency with other SCIs, omissions, or potential side
effects. A formal technical review should be conducted
for all but the most trivial changes.
 A Software Configuration Audit complements the formal
technical review by assessing a configuration object for
characteristics that are generally not considered during
review.

 Status Reporting
 Configuration status reporting (sometimes
called status accounting) is an SCM task that
answers the following questions:
 What happened?
 Who did it?
 When did it happen?
 What else will be affected?
 Status reporting provides information about each
change to those with a need to know.

Thanks!
Gagan Deep
Rozy Computech Services
3rd Gate, K.U., Kurukshetra
rozygag@yahoo.com

Software Project Planning IV

More Related Content

What's hot (17)

Viewers also liked (20)

Similar to Software Project Planning IV (20)

Recently uploaded (20)

Software Project Planning IV