Black Box Techniques
Equivalence Partitioning (EP)
Divide input into groups expected to behave same.- Example age field [0-120]:
→ Test 1 per partition = 4 cases (not all 120).
Boundary Value Analysis (BVA)
Test edges of partition.- Age [0-120]:
Decision Table
For multiple condition combinations.Condition Rule 1 Rule 2 Rule 3 Age >= 18 Y Y N Has ID Y N Y Result Allow Deny Deny
State Transition
For state-aware system (login, order).- States: LoggedOut, LoggedIn, Locked.
- Test each transition (login, logout, fail attempt).
Use Case Testing
Walk through user flow:- Successful flow.
- Alternative paths.
- Error paths.
Pairwise / All-Pairs
For many parameter combinations.- 3 OS × 3 browser × 3 country = 27 combos.
- Pairwise: ~9 combos cover all pairs (Microsoft PICT, allpairs tool).
VN context
Banking app KYC form: many condition combinations → decision table essential. Insurance quote: many parameter → pairwise.When to use
- Form input → EP + BVA.
- Business rule → decision table.
- Stateful workflow → state transition.
- Configuration combinations → pairwise.