Except the locks, opening usual keys, the entrance door can be equipped by electronic control devices of access to a premise. Conditionally it is possible to present a principle of their action as reading from object of check of certain signs which are compared to the data stored in memory of system.
The Key to such device can be and the person with its knowledge of a code to the lock or biometric signs to which carry a voice, fingerprints or all palm. The last, the truth, in our country is not applied to protection of private houses. Also as a key the card-admission can be used. Such locking devices should be by all means supplied by special input readers of the information. It is possible to apply to increase of level of protection of premises at lock-out of doors of the adaptation of different kinds.
Now some kinds of cards are widely used. Are especially popular magnetic and electronic cards. Magnetic cards are rather inexpensive, but also are least reliable, as them it is simple enough to forge or change the information written down on them.
Smart cards have the built in microprocessor and possess possibility to store bolshy, than at magnetic cards, information volume. Their price above, but thus they possess bolshej degree of protection against a fake or "тчыюьр". .
There are plastic cards with a magnetic strip . By means of the special device the information on its owner registers in one of three paths of a card. It can be both his name and a surname, and a digital code. At use of magnetic cards it is necessary to remember that at its hit in the field of electromagnet action all data stored on it is erased. It is necessary to preserve such card and against mechanical damages as the small scratch can put it out of commission.
One of the most widespread kinds of electronic locks for an entrance door now is the device as a key to which serve so-called intellectual tablets .
The tablet Case is made of stainless steel, and has diameter of 16,3 mm, and height - 3,2 or 5,8 mm. In the case there is a microcircuit with constant and operative memories (ROM and the RAM). In ROM the unchangeable code, and in the RAM - data on the owner of a key registers. Popularity of tablets is provided with their low price and the convenient size. .
The vigand-card Gradually enters into the use by owners of private houses of our country widely used abroad . Between two thin sheets of plastic 2 numbers of a thin wire from ferromagnetika are located. The information on such card is stored in a kind of a binary code: units, in other - zero in the same row register. Cards of this kind is better are protected from a fake as the alloy structure is coded by the American firm-manufacturer.
, the proksimiti-card is very convenient for identification it is not required which close contact to a reading device . The lock incorporates to the device surrounding with a zone of a radio emission to which the card reacts a signal with the password. At coincidence of a signal of a card to the information stored in memory of the input reader, the door opens. .
The proksimiti-card structure can include a battery which allows it to answer an input reader signal on considerable distance. Such card is called as active. On the passive card which is not containing batteries, the information can be written down unitary, unlike an active card which gives in to rewriting. Change of batteries is necessary for making once in 5 years. The main advantage of proksimiti-cards is that they are subject to damages less, than cards of other kinds as contact to a reading device on distance.