Operation and Maintenance
Operation —> Change
- maintain software after (and during) user operation
- integral part of process
- determine whether product as a whole still functions correctly
Difficulties
- design not extensible
- lack of up-to-date documentation
- personnel turnover
Verification and Testing
- extensive review to determine that change is made correctly and all documentation updated
- test to determine that change is correctly implemented
- test to determine that no inadvertent changes were made to compromise system functionality (check that no affected software has regressed)