Software Maintenance

• Software Maintenance is an activity in which program is modified after it had been put into use.

• In Software Maintenance usually it is not preferred to apply major software changes to system’s architecture.

• Maintenance is a process in which changes are imp0lementd by either modifying the existing system’s architecture p\or by adding new components to the system.

  Types of Software Maintenance

  Various types of Software Maintenance are

1. Corrective Maintenance: Means the maintenance for correcting the software faults.
2. Adaptive Maintenance: Means maintenance for adapting the change in environment (different computers or different operating systems).
3. Perfective Maintenance: Means maintenance or enhancing the system to meet the new requirements.
4. Preventive Maintenance: Means changes made to improve future maintainability.

Above figure shows that the making some modifications in the existing system or adding some new functionalities is very costly from maintenance point of view. Nearly 65% of efforts are required for such maintenance .If the operating environment gets changed then 18% of maintenance cost will be required. But repairing or correcting faults is less costly which may cost 17% of total coast effort.

According to Lientz and swanson (in 1980) and Nosek and palvia (in 1990), if new requirements are added the it needs lot of efforts to maintain such systems.