Abstract-This work develops a new basis for evaluating the reliability benefits of diverse software, based on fault injection testing. In particular, the work investigates new forms of argumentation that could in principle be used to justify diversity as a basis for the construction of safety claims. Failure distributions of two versions of diverse software under various fault conditions are revealed separately by fault injection methods, and then the common failure probability of the version-pair can be estimated. The approach is justified theoretically, and cross validated with other work. This method is also used to explain the fundamental influence of failure distributions on diversity. Furthermore, the unique capabilities of the method are demonstrated by implementation of the fault injection test on a program pair Index Terms-Software Diversity, Safety Case, Safety Critical System, Fault Injection, Multi-version, Reliability.
Abbreviations: AFRAverage failure rate CFP Common failure probability
EL
Eckhardt and Lee
FD
Failure distribution
FI
Fault injection
IFP s-Independent failures model
LM
Littlewood and Miller
MR
Meulen and Revilla
MSF
Mmodified sign function
NVP
New version-pair
RI
Reliability improvement
SFP