In our devices for arming, disarming and control are used KeeLoq FOB, with technology so-called "floating code". This technology provides almost absolute protection from hacker attacks and code cracking.
The technology is as follows. In the case of a conventional key fob formed a certain message frames when you press the button; receiver identifies the package and executes a given command. In the case of conventional keyfob when the button is pressed is a definite code package; the receiver recognizes this frame and executes the specified command. It is technically possible to adopt this package by special receiver (Graber), located in an action radius and remember it. By playing back the memorized sending an attacker could execute the same command, for example disarm the object. In the case of the floating code, the situation is different. The code generated by the key fob, is completely changed each time you press on a certain algorithm. The receiver "knows" the algorithm and recognizes in a new code package friendly key fob, and ignores the old code, if it appears. It is meaningless to intercept the message frames in a such system building; once used code word for the device life, most likely it will not happen again. If you know any number of previous packages it’s impossible predict the following, as for the floating code formation uses a special nonlinear algorithm based on a unique key is sewn in at the factory.
It is widely believed that KeeLoq FOB can be simulated in the presence of jammer, Graber-receiver and a powerful transmitter. Such a method actually exists, we will not describe it, but it only works in some special cases (more precisely, at the wrong design) and it is imperative to arming and disarming was carried out the same key fob button. In all of our devices for arming and disarming we use different buttons, which ensures different code sequences and simulation impossibility.
The only way of KeeLoq break is the so-called "brute force" - a complete combinations listing, i.e., more than 4 billion taps. But our devices are protected from this. The receiver detects an attempt to brute force combinations; receiving at the same time for a while blocked and transferred a notice of an attempt to hack to the desk.
When using the key fobs with floating code you need to know the following. The key fob (transmitter) and security device (receiver) must always be synchronized to use the same code combination and change it at the same time, each time you press the key fob button. If you press the key fob button when it is out of range of the receiver, it will change its combination, and the receiver that does not know to press, not change it. This will cause the receiver not identify "friendly" key fob, as it will issue the wrong code word, which is expected. In our devices are provided for a window when the key fob, even if it’s out of sync, still considered "friendly". You may accidentally while out of range of the receiver, press the button no more than 15 times, it is considered valid. Since just over 4 billion possible codes, then reducing this number by 15 only slightly reduce the cryptographic strength.
In case, if the key fob and receiver out of sync yet occurred or, for example, when changing the key fob batteries, you need to re-connect the key fob to the device. Operation is simple, and is described in the user manual for your device. But to link to our device can only our own production key fob, which registered a unique key of this device. In total you can link to device a few key fobs (from 9 to 63 depending on the device type), commands from each key fob are unique and logged and transmitted to the desk with its user numbers.
In our devices, the key fobs have an additional function - emergency call for help. In case of an attack you can invisibly (e.g., holding your hand in your pocket) press the key fob button, and an emergency call message will go to the monitoring desk. Externally, on the device, it does not manifest itself.