In the past we have seen studies exploring the possibility of transferring or extracting data from a system using sound, often with malicious purposes. While it is an attack vector with many limitations and a long list of requirements, there seems to be some beneficial potential behind this technique. Google has decided to apply it in a curious Chrome extension called Tone, which allows sharing links between computers by generating a specific sound.
Suppose someone asks you for a link to a page. The most common way is to share it via email or messenger. Searching for it on Google is not an option if the link is private, which leads us to a single conclusion: sharing links is more complicated than it should be. Now, let's move this to a collaborative environment. Pausing to share links with files and documents can cause a significant loss of time, and nobody wants that. With that in mind, a group of engineers under Google's wing designed the first prototype of Tone in an afternoon, an extension compatible with Chrome that shares links between computers by emitting sounds.
How Tone works
Basically, Tone's operation is similar to that of our voice. It even works with very low volume levels or in Hangouts sessions, but the goal is not to go through walls. The first version was very efficient, although it produced a horrible sound, so the next step was to move part of Tone's mechanism outside the human auditory range. The system also includes DTMF technology, which helped improve reception quality among multiple microphones, optimized by default to capture voice. Still, Google Tone has to yield to multiple variables. From the position of the computer to the sensitivity of the microphone, including the acoustic properties of the room, the volume of the speakers, and external noises, all affect performance.
Still experimental
Google Tone is an experimental extension, and as such it is logical to find some rough edges. We are still not sure why, but Tone requires you to log into your Google account before sharing links, and if the computer cannot "hear itself" when emitting the sound, it will show an error message. Add to this certain unexpected crashes under Chrome 42, which should be solved with a simple update to Chrome 43.
