"Ipad is locked," said a message on the home screen.
When they arrived for the morning shift on October 3rd, they found the gates locked and a message on the factory's information number saying that the factory was closed.
In simple terms, one key is used to lock the message, and the other is used to unlock it.
Lucie generates its symmetric key, say, and uses this key to lock secret message X: (1).
These, and other services, use algorithms to lock the messages with a code, so that they can be seen only by the sender and the person they are sent to – and the company, which promises not to share that information.
For instance, iPhone users who buy the MobileMe service can use the "Find My iPhone" feature to locate their device on a map, set a password lock remotely, display a message on the screen, make the phone ring even if the ringer is off and erase all content remotely.
With this, you can see where your phone is on a map, display a message, lock the phone or completely wipe it.
The software also lets you lock the phone, send a message and snap a photo — much like other device tracking systems such as Apple's find my iPhone, so the software may be duplicating existing smartphone functionality, depending on which device you own.
Click on the Info icon in the locator bar, and you'll be given the option to play a sound or send a message, lock your phone down, or wipe out all data on it.
To read messages sent through the PrivacyX system, recipients must have a digital certificate, a small, encrypted file that proves the identity of the recipient and sender and acts as a key by locking the message.
