Radio Frequency Identification (RFID) is an automatic identification method, relying on storing and remotely retrieving data using devices called RFID tags or transponders. An RFID tag is a small object that can be attached to or incorporated into a product, animal, or person. RFID tags contain silicon chips and antennas to enable them to receive and respond to radio-frequency queries from an RFID transceiver. Passive tags require no internal power source, whereas active tags require a power source.
RFID tags can be either passive, semi-passive (also known as semi-active), or active. Passive RFID tags have no internal power supply, semi-passive RFID tags are very similar to passive tags except for the addition of a small battery and active RFID tags have their own internal power source which is used to power any ICs that generate the outgoing signal. Most commercial RFID chips are passive emitters, which means they have no onboard battery, they send a signal only when a reader powers them with an rf signal. Once powered, these chips broadcast their signal indiscriminately within a certain range, usually a few inches to a few feet. Active emitter chips with internal power can send signals hundreds of feet; these are used in the automatic toll-paying devices that sit on car dashboards.
The purpose of an RFID system is to enable data to be transmitted by a mobile device, called a tag (RFID chips are usually attached to antennas - the chip and antenna combination is called a "tag."), which is read by an RFID reader and processed according to the needs of a particular application. The data transmitted by the tag may provide identification or location information, or specifics about the product tagged, such as price, color, date of purchase, etc. Retailers use them to track inventory.
Pets and people are getting chip implants under their skin that carry identification or medical information. Governments are beginning to use radio chips in driver's licenses and passports. The banks that are now using chips in their credit and cash cards say they make transactions more efficient – and more convenient for customers.
TagZapper and RFIDWasher are commercial devices (not yet for sale as of this writing) that are RFID deactivators.
RFID-Zapper is a DIY gadget to deactivate (i.e. destroy) passive RFID-Tags by modifying the electric component of a singe-use-camera with flash. Basically it copies the microwave-oven-method, but in a much smaller scale. It generates a strong electromagnetic field with a coil, which should be placed as near to the target RFID-Tag as possible. The RFID-Tag then will receive a strong shock of energy comparable with an EMP and some part of it will blow, thus deactivating the chip forever.
Criminals might be able to exploit RFID-chip cards – from sneaky scans on crowded elevators to high-powered scanners on the roadside that could mine passing traffic. DIFRWear sells a "blocking wallet" ensure that cards with RFID tags within the wallet can NOT be read while the wallet is closed.
As a result of the REALID act, most US state drivers licenses will likely contain RFID tags by the year 2007.
How To: Disable Your Passport's RFID Chip
Oh by-the-way, tampering with a passport is punishable by 25 years in prison. Wired.
Skimming Smartcards - The smartcard that gets you into your office with a quick swipe can be stolen just as fast. A thief activates and records the signal from your badge as he passes you on the street. He then plays the signal for the reader on your office door. Switching Digital Price Tags - In stores that use RFID-based price tags, digital shoplifters can record the data from the chip on, say, a cheap bottle of wine and then upload this info to the chip on an expensive one, resulting in a nice discount. Disabling Car Antitheft Devices - Many new autos won't start unless the vehicle detects an encrypted RFID chip embedded in the owner's key. But a thief can record the stolen signal with a cloner as he brushes past, use a computer to crack the encryption, and then hot-wire the car. Hackers can learn to probe your key fob’s forty-digit Radio Frequency Identification (RFID) code to gain access to (and even start) your car. A recent study out of Johns Hopkins University and RSA Laboratories found that hackers could crack the code using a relatively cheap device to scan a nearby key fob, gaining access to the secret string of numbers. After that, it’s a matter of using a transmitter to repeat the code over and over again until the doors open. Cloning an Implanted RFID - Implantable RFIDs are sold for medical identification and as never-lose smartcards. But just like smartcards, these chips can be cloned. In the future, a crook may be able to use the stolen signal to access medical records and other information. The RFID Hacking Underground
How to Build a Low-Cost, Extended-Range RFID Skimmer and surreptitiously read the contents of simple RFID tags.