Reliability definition: "Ability of a computer program to perform its intended functions and operations in a system's environment, without experiencing failure".

The interest to drive test campaigns focused on reliability is to obtain a system with a better quality for a same testing time.

Choosing a statistical testing based on operational profiles implies:

• Reliability test rather than test focused on defect discovering
• Guaranteed representativeness of the usage profile
• Assessment of the obtained reliability level
• Test management through reliability evaluation