The Ledger Nano S (http://ledgerwallet.com) is an intriguing little thing. It's a memory stick sized hardware device that can perform multiple tasks, including being a secure bitcoin wallet, an ethereum wallet, and also a hardware authenticator for the universal second factor authentication standard.
Thanks to Ledger for sending this Nano S for me to look at. Alright, let's get to it.
On first glance, this looks like an ordinary flash drive, but if we swing open the metal cover, you'll see there is a little screen and two buttons, along with a micro USB port on the end.
The interface is intentionally simple and easy to use. You use the left or right button to scroll through options, and you press both buttons to confirm a selection.
Setup is really simple. First, just plug in the micro USB cable into the side of the Nano, and you'll see the logo pop up.
It will then ask you to choose a PIN number. You will need to input this PIN every time you power on the Nano. It's worth stating that if you enter the wrong PIN 3 times in a row, it automatically erases everything on the stick, so don't forget it.
Next, the Nano gives you 24 different words to write down on the card provided. These are the recovery words which enable you to restore your generated keys in case you lose or accidentally reset the stick.
It then asks you a bunch of questions to test whether you've written your recovery words down. After that, you're ready to use the device.
Ledger has it's own Bitcoin wallet app that works in Chrome. I think there are a few other compatible wallets out there, but I tested on Electrum and couldn't get it working. The Chrome app though, seems to be a very polished experience, I just wish it was available in other browsers.
You will need to have the Nano S connected for the wallet to load up. The rest is just like a regular wallet, but when you want to send a transaction, you have to first confirm it on the device, adding a great level of physical security.
The cool thing about this is that all the important keys and sensitive data is always stored on the Nano itself, so in theory it doesn't matter if the computer you use it on is riddled with bitcoin-stealing viruses, or compromised some other way - it still remains secure.
This also means that you can plug it into any computer with access to chrome and the Ledger wallet app, and still have access to your account.
Ledger also has an Ethereum app available, which acts in a very similar way. Since the source code is open too, it's possible for third parties to create other apps for different cryptocurrencies.
The other app on the device is called FIDO, and this is the universal 2nd factor authentication system which allows you to securely log into websites. This works similar to a Yubikey, and is compatible with sites like Dropbox, Google, Github and others.
To use this feature, you need to set up two factor authentication first, then you can pair your device with your account. Then whenever you want to login, you enter your username, and password, and confirm the login by pressing the button on the Nano.
The hardware is also compatible with the emerging BitID login system, which uses Bitcoin keys instead of passwords to access accounts, though this is a very early stage protocol and is hardly used at the moment.
It's my first time using hardware like this, and I must say I really like it. There's something reassuring about having your private keys being secure and isolated on a device. The authentication process is pretty straightforward too.
If I had a wish list for the Nano, I'd definitely like to be able to use it on something other than Chrome, though this is more to do with Firefox and other browsers not adopting the same web standards. It would also be nice if they added extra features to make it even more useful, like perhaps a hardware password manager, or a way to auto sign and encrypt files using the keys on the stick.
What do you think?