Calls: Send in your ideas. Deadline August 1st, 2023.

Subliminal Messaging

Embedded secure channels within traditional and internet telephony

Most of todays telephony consists of digital transmissions, so given a codec without mangling or added noise, it becomes possible to treat (part of) that as a data channel, and pass meaningful data through it while maintaining an acceptable noise floor to the sound being transmitted. That data channel can give rise to information exchange, including key material and alternative contact options.

The project will work on various improvements that connect telephony and digital communication: (1) VPN setup with telephony protocols, (2) data communication over the PSTN backbone and its extensions into VoIP, (3) digital security for PSTN and VoIP calls.

Run by OpenFortress BV

Logo NLnet: abstract logo of four people seen from above Logo NGI Assure: letterlogo shaped like a tag

This project was funded through the NGI Assure Fund, a fund established by NLnet with financial support from the European Commission's Next Generation Internet programme, under the aegis of DG Communications Networks, Content and Technology under grant agreement No 957073.

Navigate projects

Please check out NLnet's theme funds, such as NGI Assure and NGI Zero Entrust.

Want to help but no money to spend? Help us by protecting open source and its users.