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Title: DFSSD: Deep Faults and Shallow State Duality, A Provably Strong Obfuscation Solution for Circuits with Restricted Access to Scan Chain
Abstract—In this paper, we introduce DFSSD, a novel logic locking solution for sequential and FSM circuits with a restricted (locked) access to the scan chain. DFSSD combines two techniques for obfuscation: (1) Deep Faults, and (2) Shallow State Duality. Both techniques are specifically designed to resist against sequential SAT attacks based on bounded model checking. The shallow state duality prevents a sequential SAT attack from taking a shortcut for early termination without running an exhaustive unbounded model checker to assess if the attack could be terminated. The deep fault, on the other hand, provides a designer with a technique for building deep, yet key recoverable faults that could not be discovered by sequential SAT (and bounded model checker based) attacks in a reasonable time.  more » « less
Award ID(s):
1718434 2200446
NSF-PAR ID:
10197816
Author(s) / Creator(s):
; ; ; ; ; ;
Date Published:
Journal Name:
2020 IEEE 38th VLSI Test Symposium (VTS)
Page Range / eLocation ID:
1 to 6
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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