RFID technology that allows the remote identification of travellers in moving vehicles is being rolled out at US land border crossings this month. Crossing points with Canada at Blaine, and with Mexico at Nogales, came online last week, with Buffalo, Detroit and San Ysidro to follow, and a total of 39 planned.

The system uses the US PASSport (People, Access Security Service) card, which is intended to operate within the Western Hemisphere Travel Initiative (WHTI) for US citizens entering the US via land and sea ports. Using "Vicinity RFID" it can read the cards from a healthy skimming distance of 20-30 feet, but according to the Department of Homeland Security this isn't a problem. The RFID chip on the card doesn't contain any personal information, only a unique identification number, and skimmers wouldn't have access to the data the number matches up with.

The system is intended to work like this. As a vehicle approaches the border post, the numbers of the cards inside it are read, and pictures and data on the holders are called up from a database. Then, presumably, the immigration officers check the faces of the passengers to make sure they match, and bust any who happen to be flagged as terrorists or loose criminals.

In addition to the PASSport card, some US states are beginning to issue Enhanced Driver's Licence/ID cards (EDL/ID), which have the PASSport RFID functionality added to a standard driver's license. These can also be used for land or sea entry to the US, but neither variety of card is valid elsewhere, or for WHTI air travel into the US. Obviously, they'd only be of any use at anybody else's border post if there were compatible readers there, and if the US had kindly shared its ID database with the relevant country.

So it's an internal passport system, one that's entirely incompatible with the biometric ID system that the US has gone to such pains to get the world to adopt. Were they only kidding, then? ®