Time-based OTP with Arduino
One-time-password (OTP) and its time-based version (time-based OTP, or simply TOTP) are commodity solutions to provide a second factor, in addition to simple passwords, for authentication.
Here Jose Damico proposes his way to implement a simple TOTP device using only open-source tools. The core of the project is an Arduino board connected to a small LCD. From the software perspective, the SHA-1 library comes from Cryptosuite, a cryptographic library for Arduino.
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