Analog computing is computation performed by continuous physical phenomena, such as light, voltage, current, motion, or pressure, rather than by discrete instructions and binary states. In an analog system, the machine “calculates” because the physics of the setup evolves in a controlled way. The optical feedback fractal example shows this clearly: repeated light paths and calibrated components can generate structured output without a conventional digital processor.
For cyber security, analog computing matters because security is not limited to software. Physical systems can leak information through side channels, be altered by noise or misalignment, or be pushed into unstable behavior by fault injection. Attackers may exploit timing, power, electromagnetic, or optical behavior to observe secrets or disrupt control loops. Defenders use the same physical understanding to harden sensors, isolate signal paths, and validate calibration. In short, analog computing reminds security engineers that computation can happen in hardware realities, not just in code.