Information Technology Reference
In-Depth Information
•
Technical and hardware problems
•
Corporate mergers and acquisitions
•
Government regulations
•
Change in the operating system or hardware on which the application runs
•
Unexpected events, such as severe weather or terrorist attacks
Most companies modify their existing programs instead of developing new ones because
existing software performs many important functions, and companies can have millions of
dollars invested in their old legacy systems. So, as new systems needs are identified, the burden
of fulfilling the needs most often falls on the existing system. Old programs are repeatedly
modified to meet ever-changing needs. Yet, over time, repeated modifications tend to inter-
fere with the system's overall structure, reducing its efficiency and making further modifi-
cations more burdensome.
Types of Maintenance
Software companies and many other organizations use four generally accepted categories to
signify the amount of change involved in maintenance. A
slipstream upgrade
usually
requires recompiling all the code, allowing the program to run faster and more efficiently.
Many companies don't announce to users that a slipstream upgrade has been made. A slip-
stream upgrade usually requires recompiling all the code, so it can create entirely new bugs.
This maintenance practice can explain why the same computers sometimes work differently
with what is supposedly the same software. A
patch
is a minor change to correct a problem
or make a small enhancement. It is usually an addition to an existing program. That is, the
programming code representing the system enhancement is usually “patched into,” or added
to, the existing code. Although slipstream upgrades and patches are minor changes, they can
patches come from off-the-shelf software vendors, such as Microsoft. According to the chief
technology officer of a California law firm, “Overall, we were astounded with the quantity
and size of the latest patches. This month's patches will cost us over 100 hours of IT time to
test and apply.” A new
release
is a significant program change that often requires changes in
the documentation of the software. Finally, a new
version
is a major program change, typi-
cally encompassing many new features.
slipstream upgrade
An upgrade that usually requires
recompiling all the code, allowing
the program to run faster and more
efficiently.
patch
A minor change to correct a problem
or make a small enhancement. It is
usually an addition to an existing
program.
release
A significant program change that
often requires changes in the
documentation of the software.
version
A major program change, typically
encompassing many new features.
The Request for Maintenance Form
Because of the amount of effort that can be spent on maintenance, many organizations require
a
request for maintenance form
to authorize modification of programs. This form is usually
signed by a business manager, who documents the need for the change and identifies the
priority of the change relative to other work that has been requested. The IS group reviews
the form and identifies the programs to be changed, determines the programmer who will
be assigned to the project, estimates the expected completion date, and develops a technical
description of the change. A cost/benefit analysis might be required if the change requires
substantial resources.
request for maintenance form
A form authorizing modification of
programs.
Performing Maintenance
Depending on organizational policies, the people who perform systems maintenance vary.
In some cases, the team who designs and builds the system also performs maintenance. This
ongoing responsibility gives the designers and programmers an incentive to build systems
well from the outset: If problems occur, they will have to fix them. In other cases, organiza-
tions have a separate
maintenance team
. This team is responsible for modifying, fixing, and
updating existing software.
In the past, companies had to maintain each computer system or server separately. With
hundreds or thousands of computers scattered throughout an organization, this task could
be very costly and time consuming. Today, the maintenance function is becoming more
automated. Some companies, for example, use maintenance tools and software that will allow
them to maintain and upgrade software centrally.
maintenance team
A special IS team responsible for
modifying, fixing, and updating
existing software.
