RFID (Radio Frequency ID) enables wireless data capture and transaction processing. Our last column discussed proximity applications, used primarily for access control. This time, we'll take a look at what are broadly defined as vicinity, or long-range applications, used for product tracking, inventory control, product authentication, etc.

One of my favorite applications is in libraries. Instead of the traditional librarian checking out a book - older readers will remember the card slipped into a pocket inside the cover, on which you could read previous borrowers' names hand-written along with the check-out and return dates - or the bar-code system that replaced the cards a generation ago, RFID technology allows libraries to lend and return books and other media automatically. The authorized borrower - anyone with a library card - can take a book, video, or CD and check it out without taking the librarian's time (or your own, which in my youth was wasted standing on line every Saturday morning waiting to return last week's book and check out this week's choice). When you return it, it's automatically checked back in.

The central computer processor tracks all loans and returns, giving the library real-time knowledge of inventory. It automatically alerts staff to late returns or missing books, saving staff time and improving accuracy in tracking them. And it can disallow a borrower from taking out anything if it shows that other items have not yet been returned, whether to maintain a limit on the number of items a borrower can check out at one time, or because of overdue items still in his or her possession.

Another application, which is having a wide-ranging impact on the garment world, is the incorporation of RFID tags into clothing and accessories. With so much manufacturing having moved overseas during the past two decades, it's more important than ever to protect the integrity of product lines. Not doing so opens the door to knock-off imports that cut into the bottom line, cheap copies hurting the reputation of a well-known brand-name, and use of banned components such as toxic dyes in fabric or children's toys.

By incorporating an RFID tag into a label, or even sewing it into a suit or pocketbook, a brand owner can identify its source from among dozens of manufacturing locations, thus simplifying tracking its origins. This is especially important if a product batch is inferior, allowing the brand owner to easily locate the problem.

The tag can also certify the product as authentic to identify and control counterfeits, and simplify the process of distribution, store returns, and sales data. And, at the retail end, the ID attached to each individual product can reduce in-house theft.

In airports, according to another RFID specialist, Rafsec.com, "many airlines have run RFID trials over the past few years to prove the efficacy of the systems employed in the air transport environment. Tests have shown first-read rates of over 99% with RF tags compared to less than 90% for bar code-only tags."

One of the benefits Rafsec highlights is that the tags can be recoded (using a rewrite function) at different points in the system. "This makes it possible to hold bags for security checking and release them for loading when checked, provided the RFID system is linked to the baggage reconciliation systems. Similarly, RFID is already being used to track passenger progress through airports, reducing the number of passengers arriving late at the gate and in so doing ensuring that planes leave on time."

I anticipate a wider range of uses for RFID systems in the future. While some might cost more than the systems they replace, they should be easy enough to implement and well worth the expense. For example, police departments have long urged bicycle owners to engrave a serial number on an attached tag or on the frame itself. If the bike is stolen and turns up at a pawn shop or flea market, the registered number can help track the thief and return the bike to its owner. An RFID tag can be incorporated into each bicycle sold, and reputable pawn shops can be linked to a control system in the police department - or the police can carry a portable unit, similar to that used for writing parking tickets, to check merchandise and discover thefts.

Some school boards are issuing RFID tags to students to control access to buses and school facilities, and it would be equally simple to install RFID systems in homes, replacing traditional locks and keys and even touch-key access control systems.

One of my favorite possibilities - and one that will no doubt raise the hackles of privacy advocates - is human implants. One company in Canada has already pioneered the process, though its success and long-term value is still far from being proven. But I can envision a day when every member of a family is implanted (after all, time-release implants are already in wide use to help people stop smoking or for birth control) with an RFID chip. A central computer can control access, not just to locked doors but to other items or products in a home: computers, a liquor cabinet, dangerous tools (power saws, etc.), or even a gun cabinet. Each person's chip can be encoded to allow or prevent access, protecting the home and its occupants.

When these applications will begin to appear is a question that's impossible to answer; whether they will is easy: they will, and we should all be ready for them.