Daniel Jones
Sep 22, 2016 · 3 min read

We’re all familiar with the everyday frustration of entering Wi-Fi passwords: typing a cryptic jumble of alphanumeric characters on an under-sized screen, often to be greeted with a dispiriting “Incorrect password” dialogue.

At Chirp, we believe that everyday tasks like this should be seamless, simple, and joyful. That’s why we’ve developed a technology that’s all about making things frictionless. Why enter a complicated code when your devices can simply speak to each other, without you typing a single digit?

It’s for this reason that we’ve devised a system for visitors to connect to our Wi-Fi network using nothing but a melodic authentication tone, transmitted via Chirp technology. It’s secure and seamless sign-in, reimagined by the Internet of Sound. No typing in passwords, no pre-installed custom apps. And it works on any modern device.

Here’s a demo.

Technical overview

So how’s it accomplished? Behind the scenes, we have a router hosting a restricted connection to our local network. This serves up a webpage incorporating the Chirp Javascript SDK, with a unique token that authenticates the mobile device.

When the device chirps the token, it’s heard through the router’s microphone, decoded by our Linux SDK, and relayed to the local firewall. This verifies the token and grants access to the device — and generates a short “OK” tone in response, signalling that you’re now connected.

Authentication by colocation

This approach to authentication gives some nice affordances. The first is that it’s totally effortless. Just hit “Chirp”, and the tone does the rest. As long as you’re within hearing range — say, a few metres — it just works.

As a network operator, you only want people who are in your space to be able to access it, and that’s the unique strength of this approach. You’re authenticating by your presence: to sign in, you need to be physically colocated with the router for it to hear your chirp.

This means that, if you run a hotel, you can restrict usage of your Wi-Fi to your guests (signing on within their rooms, or in the hotel lobby) whilst not requiring any cumbersome passwords. If you limit each device to a 24hr access period, you can even ask visitors to return to the lobby to re-authenticate each day.

It’s also secure. By using Time-based One-time Passwords, each code is effectively unique and linked to the current timestamp, so it can’t be recorded and reused (think Google Authenticator).

And finally, the use of an audible melody makes the whole experience tangible and humanised, just like the call-and-response interactions of birdsong. We think it transforms a moment of frustration into a moment of joy.

If you’d like to hear more about integrating Chirp into your digital ecosystem, including introducing passwordless sign-in to your own Wi-Fi network, get in touch. Ask us about our new ultrasonic SDK range — inaudible to human ears!

Chirp is the world’s most trusted acoustic proximity technology, with robust and marketing-leading SDKs for iOS, Android, Python and Javascript.



Written by the team at Chirp, the world's most trusted data-over-sound technology used by the leading brands in over 90 countries. Find out more at www.chirp.io

Daniel Jones

Written by

Chief Science Officer (Chirp)



Written by the team at Chirp, the world's most trusted data-over-sound technology used by the leading brands in over 90 countries. Find out more at www.chirp.io

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