Whether you agree or disagree with last week's story in the Wall Street Journal portraying Wal-Mart's RFID rollout in a negative light (see RFID Program at Wal-Mart Going Slow, Wall Street Journal Says; Xterprise CEO Rebuts Negative WSJ Article), we can agree on one thing: they got part of the technology story wrong.

The article states: "...bar codes help track inventory and can match a product to a price, but they lack the electronic tags' ability to store more detailed information -- such as the serial number of a product, the location of the factory that made it, and when it was made and when it was sold."

Yes and no. Some RFID tags are of course capable of storing such information - but the ones being shipped to Wal-Mart do not. They are encoded basically with a UPC number to identify the product, and a serial number to uniquely identify that container (carton or pallet).

Any additional information about where the product was located, when it was sold, etc. comes from looking up this information in a database that uses the tag to trace the lifecycle of a case or pallet of goods. This could also be done with a bar code as the database key, and thus has nothing to do with RFID per se. You could hand key the number in.

Some companies are putting much additional information on different types of RFID tags, but the Electronic Product Code (EPC) approach in retail from the beginning was to have this other information be available through databases accessible through the Internet.

And it is of course possible through longer bar codes or two-dimensional codes to capture some of this information in bar codes themselves, though this requires manual scanning, which RFID does not generally.