PCI PTS: The "Other" PCI Standard

A 403 Labs QSA, PCI Columnist Walt Conway has worked in payments and technology for more than 30 years, 10 of them with Visa.

I wonder if PCI PTS might be the Rodney Dangerfield of PCI. Merchants know its big brother, PCI DSS. But from what I can tell, not as many are familiar with PCI PIN Transaction Security (PCI PTS). That is a shame. Even though PTS is primarily aimed at device manufacturers, it has implications for every retailer with PIN pads at the point of sale (POS).

This standard defines the security requirements for both attended and unattended terminals. PCI PTS benefits retailers because it gives them a shopping list from which to choose installable devices. CIOs and acquirers: Ignore this list at your peril. If you install non-compliant devices, the card brands will hold you liable in the case of a device or PIN compromise.

Last year, Visa moved its Payment Application Best Practices (PABP) program to the PCI Council and it officially became the PA-DSS. In a parallel, long-planned action, the card brands have merged their individual requirements into this common standard and moved the PIN encryption device security requirements to the Council.

The Council's plan was to combine three separate but related sets of requirements for Point of Sale PIN Entry Devices (PED), Encrypting PIN Pads (EPP) and Unattended Payment Terminals (UPT). On May 12, the Council released version 3.0 of the PCI PIN Transaction Security (PTS) Point of Interaction (POI) security requirements. I guess that makes the "short" version of the name PCI PTS POI. Because that acronym sounds too much like a cross between the output from an Enigma machine and a barely edible Hawaiian dish, I'll just call it PCI PTS.

What this new standard means for device manufacturers is a common set of requirements for any PIN entry device used by a cardholder, including attended and unattended points of sale.

PCI PTS addresses PED security. At one level, PTS is concerned with the device itself, including both physical security (making sure it is tamper proof) and logical security (making sure the bad guys can't plant additional software to, say, transmit a PIN or encryption key). At another level, the standard addresses device use over its lifecycle, covering all functions through initial key injection. An important point to remember is that the card brands continue to own security requirements for processing and managing the PINs themselves.

PCI PTS accomplishes one other cool thing. It allows terminal or kiosk or other manufacturers to purchase PCI-approved secure components from various vendors and integrate them into a new product. That product, in turn, can be approved against the PCI PTS security requirements.

What it means for retailers is they have an approved shopping list for PEDs, whether installed as standalone devices or as components of other systems like self-service kiosks. Indeed, any PED that isn't used in an ATM is covered by this standard.

Merchants (and their acquirers and ISOs, too) need to be careful that any PEDs they install are on the Council's approved list. Unfortunately, based on my experience, using that list can be a bit daunting. It specifies manufacturer, model name, hardware version number, firmware version number and an application version number, where applicable. It then gets more confusing because, as the Council warns, "Acquirers, merchants and their agents should be aware when making purchasing decisions that some vendors may sell the same model in both approved and unapproved versions."

If you don't follow the Council's shopping list, the downside is that you will be financially liable if your PED is breached.

I expect vendors will build to the new PTS specs right away, because they become effective in one year (May 2011). Although you can buy currently validated equipment until that time, why would you? If you are looking at a terminal (think kiosk, gasoline pump, vending machine) that combines several individual components, you'll want to check each component (including software) against the Council's list, noting version numbers.

I also suggest getting something in writing from the seller that indicates every component associated with the PED has been assessed by a PCI PTS lab and is compliant. Lastly, check out Visa's recently issued FAQ for merchants evaluating and buying PEDs.

On a side note, it is interesting that the PCI Council plans a three-year lifecycle for the PTS. This stance may telegraph increasing the current two-year DSS lifecycle when it is revised in October.

With PTS, the PCI Council has taken a step toward closing the loop on protecting the entire transaction process: PTS protects the cardholder's PIN; the DSS protects cardholder data stored, processed or transmitted by the merchant; and PA-DSS provides secure payment application. At the same time, the Council has simplified the retail CIO's purchasing decisions by providing a pre-tested "buy list" from which to assess individual PEDs and even integrated terminals.

Maybe we all should consider PTS to be a little less like Rodney Dangerfield after all.

What do you think? I'd like to hear your thoughts. Either leave a comment or E-mail me.