Behind Bars

Education needs of healthcare product packagers. Source: PMP News’s 2006 Security Packaging Survey.

Bar codes may be used for more than just product identification. They may also play a role in product authentication.

“Unique visible bar codes can be used very cost-effectively for authentication, if done with an appropriate secure encoding scheme, for very low cost,” says Robert Rack, president of RDG/BarCodeAmerica.com. “Unique non-human-visible codes and reading devices can be used for a slightly higher material and reader cost, but with additional security.”

Respondents to an exclusive PMP News survey should welcome this news. PMP News’s 2006 Security Packaging Survey, fielded in late 2006, revealed that 39% of respondents are interested in learning more about the use of bar coded lot and date codes as part of a product security program. Twenty-six percent are interested in relying on bar coded National Drug Codes (NDC) or Universal Product Codes (UPC) as security tools. Nineteen percent are interested in mass serialization.

“A small but growing number of manufacturers are now having their primary product labels printed with unique bar codes that feature some sort of alphanumeric serialization,” reports Rack. “The smarter ones are using an embedding scheme and check-digit combination and their own unique encryption that calculates a unique check digit for authentication that takes into account the product ID, lot code, and serialized alphanumeric numbering scheme that in turn produces the appropriate check digit.” Sometimes, expiry data are also part of this calculation, he adds.

Rack says that these codes are typically visible bar codes, often either standard linear codes or Data Matrix. “Sometimes, we are also producing non-human-visible codes that might be seen in either infrared, near-infrared, or ultraviolet spectrums,” he says. “These codes allowing encryption are generally being produced using Data Matrix codes.” Rack won’t disclose the printing method he is using; he’ll only say that it is a patent-pending process that “can be done for very minimal cost, generally under 1 cent per code, versus the 15-plus cents that are spent on radio-frequency identification (RFID).”

Interest in bar codes for lot and date codes is slightly higher than that in RFID use. Thirty-one percent of survey respondents are interested in learning more about the use of RFID for cases and pallets, as 31% are interested in RFID tagging items.

“The biggest advantage of RFID is that it allows non-line-of-sight reading,” says Rack. But without an appropriate encryption method and unique calculated signature, “manufacturers are deluding themselves if they think that they have a secure encoding scheme.”

Line-of-sight reading may also work to promote product authentication. “The very fact that line of sight is required for either visible linear or two-dimensional codes is an advantage. Because line of sight is not required for RFID labeling, RFID tags are vulnerable to replication by interrogation without opening the very boxes that they are contained within. A clever counterfeiter with confederates and access to a warehouse could readily capture this information.”

The best and most secure means of authentication is likely RFID used in concert with unique serialized and calculated check-digit-authenticated bar code signatures, says Rack. “And they both can be utilized so that each helps to authenticate the other.”