Engineering sub-milliwatt authenticated encryption pipelines utilizing the winning NIST lightweight cipher ASCON.
While AES-256 is the enterprise standard, its multi-round S-box operations consume excessive energy and die area in battery-constrained wearable devices. WearableHSM implements ASCON-128, the official NIST lightweight cryptography standard, delivering equivalent 128-bit security with 75% lower energy consumption.
The ASCON permutation utilizes a 320-bit state and lightweight bit-slice operations, allowing WearableHSM to achieve wire-speed encryption of continuous 250 Hz PPG waveform streams with negligible battery drain.