Security Threats and Countermeasures for Approximate Arithmetic Computing

Approximate computing (AC) emerges as a promising approach for energy-accuracy trade-off in compute-intensive applications. However, recent work reveals that AC techniques could lead to new security vulnerabilities, which are presented in a format of visionary view. There is a lack of in-depth research on concrete attack models and estimation of the significance of the attacks on approximate arithmetic computing systems. This work presents several practical attack examples and then proposes two attack models with quantitative analysis. Input integrity check and exclusive logic based attack detection methods are proposed to address the attacks on AC systems. The experimental results show that the attack detection failure rate of our method is below $2.2*10^{-3}$ and the area and power overhead is less than 6.8% and 1.5%, respectively.