App turns smartphone into smart key

It could soon be possible to use your smartphone to remotely give someone permission to enter your house.

The ShareKey system from the Fraunhofer Institute for Secure Information Technology lets users unlock their door by waving their phone at it; and grant specific permissions via email for others to do the same.

“In essence, ShareKey offers two new functions: users can issue digital keys remotely and assign these keys certain user permissions. For instance, I can grant the building superintendent access to my apartment for a short period so that he can open the door for the gas meter to be read while I’m at work,” says Alexandra Dmitrienko.

“The solution is built around modern security technologies and can be easily integrated into existing access control systems.”

ShareKey  works using Near Field Communication (NFC), which allows data to be exchanged wirelessly over short ranges of up to a few centimeters. “To open a door, all you need to do is hold your mobile phone close to the lock,” says Dmitrienko.

To grant permissions, it sends electronic keys directly to the user’s mobile phone, in the form of a QR code attached to an e-mail or MMS.

Communication between the mobile phone and a central server is protected by established security protocols.

“And even if this communication is hacked into, it’s impossible for unauthorized people to gain access to the digital key,” says Dmitrienko. “This is because opening the door requires information contained both in the encrypted token sent to the user and in the app installed on their smartphone.”

The team sees uses for the technology in locker compartments, to help administer keys in hotels and as part of car-sharing schemes, as well as for the home.