How Hermes Uses the Ionosphere to Link Remote Communities
Short summary
Rhizomatica's open-source HERMES system lets remote communities send files, photos, and encrypted messages over shortwave radio instead of just voice, achieving 400-600 kilometer links with minimal infrastructure. The system proved itself when Bangladeshi fishers used it to coordinate a rescue after a boat broke down in the Bay of Bengal.
- HERMES transmits files at 400-600 bits per second over HF radio using the ionosphere as a reflector, enabling data transfer in places where terrestrial infrastructure doesn't exist
- The system handles practical emergency and logistical needs—GPS coordinates, SOS signals, medical data, supply lists, and evidence photos—faster and more reliably than voice transmission
- Bloom built optional encryption into HERMES because some partner communities in sensitive areas need protection from having their communications intercepted and weaponized
Full summary
Rhizomatica, a Philadelphia nonprofit founded by Peter Bloom, has open-sourced HERMES—a digital shortwave radio system that transmits data over the high-frequency band (3-30 megahertz). Unlike basic voice radios, HERMES sends files of any type: photos, emails, GPS coordinates, medical data, whatever needs moving. The system uses the ionosphere to bounce signals across 400-600 kilometer distances with just 20 watts of power, making it useful in remote areas where laying terrestrial infrastructure isn't practical. While traditional shortwave radios manage only hundreds of bits per second, HERMES improves data rates and adds optional encryption—a feature Bloom included because some of their partners operate in sensitive regions where unencrypted broadcasts could expose them to danger.
The real value shows up in concrete situations. Fishers in Bangladesh use HERMES to send GPS positions and SOS calls when mechanical problems strike far offshore. Emergency responders can receive latitude and longitude coordinates instead of trying to parse directions over crackling audio. Field workers documenting illegal logging send photos directly rather than spending days traveling to reach someone with a computer. Manifests, parts lists, telemedicine requests—anything that would take forever to read aloud becomes a simple file transfer.
The encryption question reveals something important about how regulations vary by country. Amateur radio rules differ everywhere, so Bloom made encryption optional rather than mandatory. Partners in sensitive areas can flip it on; others leave it off. That flexibility matters because the same tool serves wildly different needs—from rescue operations to human rights documentation to routine supply chain communication in places the modern world has largely forgotten about.