3. Maintenance activities
Corrective maintenance
Fixing bugs / removing errors
Adaptive maintenance
Changes to the environment in which the software operates
means necessary changes to the code. Could be updated
operating system, or new hardware
Perfective maintenance
Responding to user requests for changes in functionality or
additional features
5. Factors affecting maintenance
New applications
As users gain experience of a new application, they
will begin to see potential improvements and features.
Staff mobility
It is always easier for the original programmer to
update the code than someone else. When staff move
on, it becomes harder to maintain code unless it is
very well documented.
6. Factors affecting maintenance
Too many versions
It can be difficult to trace changes in code if there
have been a number of releases.
7. Factors affecting maintenance
Insufficient documentation
If the design documentation or internal commentary is
poor or missing, then maintenance will be affected.
It is good practice to use internal commentary and
descriptive variable names.
9. Factors affecting maintenance
External hardware and software changes
Changes to hardware platforms, or upgrades to
operating systems can affect maintenance
requirements.
10. The cost of maintenance
The cost of maintenance will obviously vary from one
project to another.
It is estimated that between 40% and 70% of the
overall software development lifecycle costs are spent
on maintenance.
