Analysis of some simple stabilizers for physically obfuscated keys

摘要

Physically Obfuscated Keys (POK) are used to embed in chips secret bit-strings to be used in cryptographic protocols. Usually a POK is built as an array of elementary 1-bit POKs (cells). In order to guarantee that the same secret bit-string is generated at every turn-on, stabilizer circuits are required, which are typically based on possibly expensive error-correction circuitry. In this paper we propose a stabilizer scheme that is not based on error-correction codes, but rather forces to zero the cells that are too unreliable and compensate for the disabled cells by means of a mixing stage.