An anti-theft system is any device or method used to prevent or deter the unauthorized appropriation of items considered valuable. Theft? is one of the most common and oldest criminal behaviours. Where the ownership of a physical possession can be altered without the rightful owner's consent, theft prevention has been introduced to assert the ownership whenever the rightful owner is physically absent. Anti-theft systems have been around since individuals began stealing other people's property and have evolved accordingly to thwart increasingly complex methods of theft. From the invention of the first lock and key to the introduction of RFID? tags and biometric identification, anti-theft systems have evolved to match the introduction of new inventions to society and the resulting theft of them by others.
Methods of Theft Prevention
There are a number of general categories of anti-theft systems:
Sequestering of valuable items
A very common method of preventing theft is the placement of valuables in a safe location. The definition of safe depends on the minimum threshold for theft as determined by the owner. Desk stationery is often considered secured if placed in an unlocked drawer away from view, while expensive jewelry might be placed in a safe behind a picture in a home.
Raising the awareness of theft
Another common method is the alerting of other individuals to the act of theft. This is commonly seen in department stores, where security systems at exits alert store employees of the removal of unpaid items. Older car alarms also fall into this category; newer systems also prevent the car from starting.
Preventing Removal of items
Yet another method is the attachment of items to a larger immobile object, usually furniture or walls.
Disabling the stolen item
Items with specific functionality can often be disabled to prevent the use of the item if it should be stolen. The anti-theft system can require disabling on every use, or enabling when the item needs to be secured. Disabling the anti-theft system is usually done by requiring identification of the owner at some stage of use. Identification can occur through physical or other means (physical keys, numerical codes, complex passwords, biometric identification). A passive immobilizer makes car theft almost impossible because the vehicle cannot be started without a computer chip that is found within the ignition key. This can work even retrospectively: as a stolen credit card can easily be invalidated with a phone call to the issuing bank, the motivation to steal one is reduced.
Security Tags
Security tags are devices that are attached to products to prevent shop-lifting. Often used in conjunction with an Electronic article surveillance system. Smart Water is another such security tag, in which fluid containing millions of tiny fragments have a unique number called "SIN" ("SmartWater identification number"), and registered in a national police database together with the owner's details, is etched into each of those particles.
Tracking Software
Electronic items such as laptops, cell phones and even gadgets such as iPods now have software that enable them to "phone home" with information regarding their whereabouts and other information that can aid law enforcement to track the devices down.
Forensic Marking
Assets can be marked with various forensic marking materials for law enforcement traceability of the item. An example of this type of marking is MicroDotDNA and Operation Hands Off.