WebRTC signaling using sound. Works with all devices that have microphone + speakers. Runs in the browser.
Nearby devices negotiate the WebRTC connection by exchanging the necessary Session Description Protocol (SDP) data via a sequence of audio tones. Upon successful negotiation, a local WebRTC connection is established between the browsers allowing data to be exchanged.
The WebRTC technology allows two browsers running on different devices to connect with each other and exchange data. There is no need to install plugins or download applications. To initiate the connection, the peers exchange contact information (ip address, network ports, session id, etc.). This process is called “signaling”. The WebRTC specification does not define any standard for signaling – the contact exchange can be achieved by any protocol or technology.
In this project the signaling is performed via sound. The signaling sequence looks like this:
Peer A broadcasts an offer for a WebRTC connection by encoding the session data into audio tones
Nearby peer(s) capture the sound emitted by peer A and decode the WebRTC session data
Peer B, who wants to establish connection with peer A, responds with an audio answer. The answer has peer B’s contact information encoded in it. Additionally, peer B starts trying to connect to peer A
Peer A receives the answer from peer B, decodes the transmitted contact data and allows peer B to connect
Connection is established
Try it yourself: ggerganov.github.io/wave-share
https://github.com/ggerganov/wave-share