Software Evolution Flashcards
What is the primary reason new systems decline in value over time?
They eventually become obsolete.
What are the four changeover methods?
Direct Cutover, Parallel Running, Phased, and Pilot.
Which changeover method has the lowest risk but highest cost?
Parallel Running.
What factors should be considered in system deployment?
Cost, time, system quality, customer impact, employee impact, and technical feasibility.
What was a key lesson from the UK Passport Office case study?
Changing requirements without adjusting timelines leads to failure.
What are legacy systems?
Outdated hardware, software, and processes still in use.
What are common legacy system issues?
Obsolete hardware, inconsistent data, embedded rules, and high maintenance costs.
What are the types of software maintenance?
Fault repairs, environmental adaptation, and adding new functionality.
Why do maintenance costs often exceed development costs?
Structural degradation, aging technologies, and high learning curves.
What is technical debt?
Future cost of rework from shortcuts or poor design.
How can technical debt be managed?
Through refactoring and following good practices.
What are the key decisions for legacy systems?
Scrap, maintain, re-engineer, or replace.
What are risks associated with legacy system replacement?
Lack of specifications, business-process dependencies, and undocumented rules.
What does DevOps aim to reduce?
Technical debt and improve maintainability.
What factors indicate a need for system replacement?
High failure rates, poor performance, outdated technology, and high support costs.
