The Target of Evaluation (TOE) under the Common Criteria provides a different level of assurance. The most crucial factor is whether it is engineered based on a design.
If a TOE is lack of design, its EAL will be under 3, while a TOE with a design will be methodically reviewed.
The EAL of a TOE with a design depends on the condition that it is semi-formally or formally designed. Formal design is usually based on a mathematical model.
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