The document discusses various topics related to verification and validation of critical systems, including reliability metrics, hazard analysis, fault tolerance techniques, and software testing approaches. It describes verification as checking that the product is being built correctly according to specifications, while validation checks that the right product is being built to meet user requirements. Various static and dynamic verification methods are covered, including inspections, static analysis, and different types of software testing.

13. The V-model of development

23. Static analysis checks

26. LINT static analysis 138% more lint_ex.c #include <stdio.h> printarray (Anarray) int Anarray; { printf(“%d”,Anarray); } main () { int Anarray[5]; int i; char c; printarray (Anarray, i, c); printarray (Anarray) ; } 139% cc lint_ex.c 140% lint lint_ex.c lint_ex.c(10): warning: c may be used before set lint_ex.c(10): warning: i may be used before set printarray: variable # of args. lint_ex.c(4) :: lint_ex.c(10) printarray, arg. 1 used inconsistently lint_ex.c(4) :: lint_ex.c(10) printarray, arg. 1 used inconsistently lint_ex.c(4) :: lint_ex.c(11) printf returns value which is always ignored

29. The Cleanroom process

43. Equivalence partitions

44. Search routine specification procedure Search (Key : ELEM ; T: ELEM_ARRAY; Found : in out BOOLEAN; L: in out ELEM_INDEX) ; Pre-condition -- the array has at least one element T’FIRST <= T’LAST Post-condition -- the element is found and is referenced by L ( Found and T (L) = Key) or -- the element is not in the array ( not Found and not ( exists i, T’FIRST >= i <= T’LAST, T (i) = Key ))

46. Search routine - input partitions

48. White-box testing

50. Binary search equiv. partitions

55. Incremental integration testing

57. Top-down testing

58. Bottom-up testing

61. Interface testing

72. Scenario-based testing -- Collect weather data

75. A testing workbench