Point-of-sale systems, where customer credit or debit cards are swiped for payment, are one of the most frequently used computing systems in the developed world.

They're also targeted by criminals. For instance, in 2005 attackers compromised POS systems at a Marshalls retail store and stole cardholder data. That same year, attackers stole the source code for Wal-Mart's custom-built POS systems. No customer data was compromised, but it's a clear indication that criminals put a bull's-eye on POS systems.

Today, attackers have only become more sophisticated, using advanced software techniques to avoid detection by antivirus software. In the physical realm, attackers attach card-reading devices, known as skimmers, to ATMs and POS devices. When users insert their cards, skimmers copy the numbers. Thieves also attach hidden cameras along with skimmers to record PIN numbers as users type them in.

Add It Up

Companies take one of three approaches to develop and deploy POS terminals: buy a purpose-built platform that usually runs on a proprietary or embedded operating system, use a common PC running Windows and a POS application, or build and deploy a custom-built POS system. They can maintain the POS systems themselves, outsource maintenance and operations, or use some combination of both.

Regardless of the approach they take, business owners typically estimate total cost of ownership based on critical features, deployment, and ongoing support. POS security is usually an afterthought. Yet if a breach occurs, the resulting costs can easily eclipse the price tag for the POS system deployment.

Part of the challenge is that it's difficult to calculate how much a breach costs. If your organization loses credit card or personal data, you incur notification, incident response, investigation, and legal costs, along with a PR nightmare, potential customer churn, and possible fines and lawsuits.

How much does that tally up to? Some researchers says a breach can cost $1 per customer record, while other sources go as high as $200. That range makes accurate calculations tricky.

That said, there are some numbers to work with. For instance, Heartland Payment Systems has set aside $73 million as a pre-tax provision for its breach costs. According to an InformationWeek article, TJX absorbed an $118 million charge to address costs related to its breach of over 45 million cardholder records in 2007.

Smart companies can estimate how much lost data might cost them and bring that number into the TCO conversation. Why? Because without factoring in the risks present in POS systems and the controls required to address those risks, the total cost of ownership can't be accurately calculated.

POS BEST PRACTICES

1. Apply sensible security operations and practices to POS devices, just as you would to other critical systems.		2. Choose POS devices approved by the PCI Security Standards Council. They aren't attacker-proof, but they'll meet PCI requirements.		3. If your POS devices are also general-purpose PCs, limit employee access.
4. If employees use POS devices for Internet access, deploy supplemental controls, such as whitelisting software so only approved applications will run, and strictly limit Web access.		5. If a third party is responsible for maintaining POS devices, follow up regularly to ensure they're doing so.		6. Consider adopting chip and pin, tokenization, and end-to-end encryption when these features become available in POS systems.