The Department of Homeland Security is experimenting with radio-frequency identification technology (RFID) to track foreigners as they enter and leave the United States. The agency hopes the technology will improve border management without delaying travelers.

RFID tags will be tested at a simulated port this spring and then at border crossings in Arizona, New York and Washington state from July through the spring of 2006. "Through the use of radio-frequency technology, we see the potential to not only improve the security of our country, but also to make the most important infrastructure enhancements to the U.S. land borders in more than 50 years," said Asa Hutchinson, Homeland Security's Undersecretary for Border and Transportation Security. The tests will help determine whether to affix RFID tags to passports, visas and other documents visitors must carry during their stay in the United States. The tags should not slow a visitor's movements through border crossings, a Homeland Security spokeswoman said. For tracking foreign visitors, RFID is said to be more efficient than current rubber-stamping technology.

To protect privacy, the tags won't hold a visitor's personal information, only serial codes linked to information stored in the Homeland Security Department's US-Visit (U.S. Visitor and Immigrant Status Indicator Technology) databases. The codes would be meaningless to any third party trying to access the information.

The tags will be tamper proof and difficult to counterfeit. Information on them cannot be changed, and they will not be activated until they are issued. All this will prevent "skimming," the use of unauthorized reading devices to capture information from RFID tags, the government says. The tags cannot be used to track visitors' whereabouts while they are in the United States.