One Wire

One-Wire (1-Wire)
Best for: Extremely low-speed, low-cost monitoring (digital thermometers like the DS18B20, iButtons).

How it works: Developed by Dallas Semiconductor, it uses just a single data wire and a ground wire. Devices can even derive power directly from the data line itself (parasitic power mode).

Speed: Around 16.3 kbps.

Distance: Up to 300 meters under ideal, low-speed conditions.