It’s not news that quantum mechanics can be used to send secret messages without concern of them being intercepted.  For years, physicists have been using this technology to do so.  However, a true quantum link has only recently been successful.  Originally, the messages were sent using quantum mechanics, but then had to be decoded at each node in order to continue the message.  Since the nodes weren’t quantum mechanical, this left the information vulnerable to hacking at each node.  A quantum link means the message never has to be decoded.  By combining many quantum links, a true quantum network could be created.  This would mean a completely unhackable telecommunications network.