Open-source HERMES boosts data rates and adds encryption to shortwave radio

Rhizomatica, a Philadelphia-based nonprofit led by founder Peter Bloom, has released HERMES, an open-source software stack that turns high-frequency shortwave radio into a general-purpose data pipe. Paired with a digital modem called Mercury and operating in the 3–30 MHz HF band, the system bounces signals off the ionosphere to establish reliable 400–600 km links using radios drawing only about 20 watts. That lets remote, off-grid, and indigenous communities in places like Bangladesh, Brazil, and Ecuador exchange files—photos, emails, voice memos, GPS coordinates—rather than relying on voice alone, with almost no terrestrial infrastructure.

The practical payoff is that structured data moves without error-prone verbal relay: crews can transmit a manifest, a telemedicine status, or photographic evidence of illegal logging directly as a file. Notably, HERMES bundles optional encryption—a feature amateur-radio rules prohibit in many countries—so partners operating in politically sensitive areas can protect transmissions from being intercepted and used against them. Users toggle it on or off depending on local law and risk.

The project’s significance lies in cheap, self-sufficient long-range connectivity for emergencies and marginalized regions. In one pilot, roughly a dozen artisanal fishing boats in the Bay of Bengal were equipped with HERMES; when one suffered a mechanical failure 100–200 km offshore, its crew transmitted GPS coordinates and an SOS, coordinating a successful rescue. The open trade-off remains the ionosphere’s variability, which constrains how Mercury balances throughput against reliable delivery.