Gilbert Goodwill, Senior Principal Engineer, DPA Team Lead, Cryptography Research, Inc. Test Vector Leakage Assessment (TVLA) is a conformance testing methodology for side-channel resistance. Instead of performing extensive black-box testing, known-data analysis is used to detect leakage, avoiding the additional work to exploit that leakage. If TVLA testing shows a lack of leakage in a device, it must be confirmed as being a result of the target of evaluation’s secure implementation and not due to inadequacies in signal isolation. In short, lack of signal should not be construed as lack of leakage.
In order to avoid falsely passing a device, a reference leakage of known unprotected or non-sensitive quantities during cryptographic processing must be measurable by that same standard. Without such a reference, a TVLA result showing lack of leakage should be considered erroneous.