In recent years, various deep learning techniques have been exploited in side
channel attacks, with the anticipation of obtaining more appreciable attack
results. Most of them concentrate on improving network architectures or putting
forward novel algorithms, assuming that there are adequate profiling traces
available to train an appropriate neural network. However, in practical
scenarios, profiling traces are probably insufficient, which makes the network
learn deficiently and compromises attack performance.
In this paper, we investigate a kind of data augmentation technique, called
mixup, and first propose to exploit it in deep-learning based side channel
attacks, for the purpose of expanding the profiling set and facilitating the
chances of mounting a successful attack. We perform Correlation Power Analysis
for generated traces and original traces, and discover that there exists
consistency between them regarding leakage information. Our experiments show
that mixup is truly capable of enhancing attack performance especially for
insufficient profiling traces. Specifically, when the size of the training set
is decreased to 30% of the original set, mixup can significantly reduce
acquired attacking traces. We test three mixup parameter values and conclude
that generally all of them can bring about improvements. Besides, we compare
three leakage models and unexpectedly find that least significant bit model,
which is less frequently used in previous works, actually surpasses prevalent
identity model and hamming weight model in terms of attack results
