SONIC CYPHER

AIR-GAPPED AUDIO DATA TRANSFER PROTOCOL.

Transmits on a near-ultrasonic carrier (17–19.6 kHz) that most adults cannot hear. Raise the volume on the sending device and allow microphone access on the receiving one. Switch to the audible band if the two devices are far apart or the speaker is weak.

SONIC NETWORK LINK

16-FSK + REED-SOLOMON FEC | REPEAT-UNTIL-ACKNOWLEDGED | CROSS-PASS ACCUMULATION | 10 baud | UTF-8

> TRANSMITTER (TX)

BROADCASTING

CARRIER BAND:

LINK: IDLE

TX FREQUENCY SPECTRUM:

> RECEIVER (RX)

LISTENING

LINK STATE: IDLE

TONE MARGIN: 0.0x

WAITING FOR SIGNAL...

RX TONE BANK (each bar is one symbol):