Information Technology Reference
In-Depth Information
introducing another fault elsewhere in the product, that is, a regression fault. If
regression faults are to be minimized, detailed documentation for the product must
be available. Having determined the probable fault, the maintenance programmer
must test that the modification works correctly and that no regression faults have
been introduced in the process. Checking for regression faults is done using a
specific set of test data stored precisely for performing such regression testing.
Next, the test cases used for modification must be added to the stored test cases.
Finally, it is essential that the maintenance programmer document every change
made to the system. The other major maintenance tasks are adaptive and perfective
maintenance. To perform these, the maintenance programmer must perform the
requirements, analysis, design, and implementation workflows, taking the existing
product as the starting point. Perfective and adaptive maintenance are adversely
affected by a lack of adequate documentation, just like corrective maintenance.
Take, for example, a situation where the product has been delivered to the client.
But, the client is dissatisfied, because the product does not work correctly, it does
not do everything that the client currently wants, or the circumstances for which
the product was built have changed in some way. It is important for every software
organization to keep its clients happy by providing excellent post-delivery main-
tenance service. So, for product after product, post-delivery maintenance is the
most challenging aspect of software production—and frequently the most thank-
less. Managers must restrict post-delivery tasks to programmers with all the skills
required to properly perform maintenance (Schach
2007
).
11.7 Managing Post-Delivery Maintenance
11.7.1 Defect Reports
Changing products is a necessity for all software projects. In order to fully
understand the changes that are necessary, defect reports must first be filed. Defect
reports are the documents that describe in what manner the product differs from the
specification. Defects in the product may range from things that are simple and
cosmetic to defects that are capable of causing injury or loss of life. Maintenance
programmers work from the defect reports which are normally collected and filed
by customer service representatives. Since, it is imperative that defect reports are
not necessarily handled in the order obtained, but in the order of importance (the
ones that have the greatest adverse consequences first) not all reports will be
handled on a first come first served basis. A manager will normally oversee the
process to ensure that the changes are occurring in the correct order. Another role
of the manager is to decide when an update should be released. As it is substantial
work to update documentation and user programs, several changes may be com-
piled into a single update. Upon a change all customers should be updated and
provided with the correct deliverable and documentation.
