advertisement
advertisement

Phone Tracking And The Law: Clear Sailing

Written by Mark Rasch
February 21st, 2013

Attorney Mark D. Rasch is the former head of the U.S. Justice Department’s computer crime unit and today serves as Director of Cybersecurity and Privacy Consulting at CSC in Virginia.

In the ongoing Nordstrom/Euclid cell phone tracking debate, it seems that Nordstrom (NYSE:JWN) failed to ask all three necessary questions when using any technology that might raise a privacy concern. These questions are, in no particular order: Is it legal? Is it profitable? And is it wise? Ask only two of these three questions, and you can be in deep trouble.

The debate surrounds the Seattle-based retailer’s use of a vendor called Euclid, which captures information from the Wi-Fi signals of both customers and passersby.

Is it legal?
There is no specific U.S. law on whether MAC addresses are “personal information” entitled to legal protection. Moreover, U.S. law regarding things like access to cell phone records and cell phone usage probably don’t apply to the Wi-Fi portion of the device. So although it may constitute an unlawful “trap and trace” or “pen register” to capture a cell phone number or IMEI of a cell phone, these laws likely don’t apply to capturing the MAC address of a Wi-Fi-enabled device. Put simply, your iPad or Wi-Fi-enabled iPod isn’t a phone, nor is the non-phone portion of your iPhone, Blackberry, Android or Windows mobile device.

So the “ping” is probably legal. Or better yet, probably not expressly prohibited under current U.S. law (lawyer tip—always equivocate. Always.).

The next question is whether a MAC address is “personal information.” Generally, a MAC address would not be considered personal information, any more than the serial number of your toaster would be personal information. It identifies a device, not a person, and it reveals no information about that device except the manufacturer and that it is a device. Big fat hairy deal, right?

But a Wi-Fi-enabled device does reveal a lot more than a toaster. And a MAC address can reveal intimate personal information, depending on how it is used and what information it is used with.

For example, Valentine’s Day was last week, and you and your girlfriend (each with a separate device) strolled into Nordstrom. The Euclid sensor picks up the unique MAC addresses and follows the two unknown devices into the store. Yours veers off to hardware (I know, Nordstrom doesn’t have hardware, but stay with me here) and hers walks to to women’s shoes. Hmm. I detect a pattern. You then meet at jewelry and stay there for about 15 minutes. You leave together. Personal information? Maybe.

A few hours later, your MAC address again pings the store. This time, it’s accompanied by an entirely different MAC address. This time, it’s your wife’s MAC address. Busted! Hard to say that the MAC address with the traffic data is not, in some way, “personal.”

Now we add the anti-theft cameras, the parking lot cameras capturing license plate information and even the registers themselves. Pretty easy to turn an anonymous MAC address into a real-life, real-time profile of a specific person. And each bit of information is perfectly legal to capture.


advertisement

6 Comments | Read Phone Tracking And The Law: Clear Sailing

  1. David Sheidlower Says:

    Another great article, Mark. But I think the idea that it is not difficult to opt out of being tracked by going to a web site and typing in your MAC address is a bit of a stretch.

    I’m not sure that most users can just grab their MAC addresses off their devices. Consider how much work the credit card industry has done in the past few years to get people to notice the three digits on the back of their cards (CSV#). Teaching people to learn what a new identifier is, how to find it, and what it is used for may not be as simple as you think.

  2. Mark Rasch Says:

    David

    I tried to opt out FROM MY iPhone. The problem was switching back and forth between the website (and the CAPTCHA) and the settings to get the MAC address. Also, there’s a difference between a Nordstrom CUSTOMER opting out, and a passer by who has no idea that the data is being captured at all. How about a giant sign, “warning — big brother is watching! To opt out, do the following…?”

  3. A Reader Says:

    Mark,

    Imagine that your cell phone is repeatedly playing “I’m Mark Rasch. I’m Mark Rasch.” out of its speaker, or has a projector shining “Mark Rasch” on the ceiling and floors wherever you walked. There’s no difference between this and the WiFi broadcast other than plain old eyes and ears can’t detect it. But it’s equally there.

    You’re the one who purchased and is voluntarily carrying the device that is continually spraying “I’m 12:34:56:78:90:AB” across the 2.4GHz band. You may have the device for your own convenience. It’s entirely your choice to have the device and have the WiFi radio turned on.

    If you want to “opt out”, turn off your WiFi. And your Bluetooth. And your cellphone. And remove any RFID responding devices you have from your person, including your credit and transit and door entry cards, any RFID tags sewn into your garments, and perhaps even your car keys. And if you’re going that far, you might want to wear “CV dazzle” makeup to hide from all the cameras watching virtually every public space you enter.

    Surveillance is now ubiquitous in the public square. Does it make sense to try to ignore it?

  4. Mark Rasch Says:

    I agree that surveillance is now ubiquitous in the public square. It doesn’t make sense to ignore it. It does make sense to try to balance that with rights to privacy. I transmit my MAC address in order to obtain a signal and to log on to a service. In doing so, I do not expect to create a permanant record, available to everyone at all times of my location and movements. The logic of “you are broadcasting it so it can’t be private” can apply to (and has applied to) location data as well as the contents of cordless phone conversations. IMHO, you CAN have an expectation of privacy in public spaces — its a matter of defining its parameters.

  5. Evan Schuman Says:

    And as bad as it is today, get ready for it to get a LOT worse. Here’s a wonderful piece over at TheStreet.com about Google Glass: http://www.thestreet.com/story/11850432/1/watch-out-for-google-glasses.html

  6. Marty Ramos Says:

    Doesn’t V/MC already market credit card data such that one retailer can see visits to various other retailers…

Leave a Reply

Readers, specifically those who want to comment on a story:
Our Comment SPAM system is getting very aggressive these days and has been blocking legitimate comments. If you post a comment and don't see it appear within 2 hours or so, can you please send a heads-up to customer-service@storefrontbacktalk.com? Ideally, please include the time you posted the comment. That will allow us to try and hunt for it. Thanks! P.S. We're working on fixing the system, but we don't want to lose any valuable comments in the meantime.

Newsletters

StorefrontBacktalk delivers the latest retail technology news & analysis. Join more than 17,000 retail IT leaders who subscribe to our free weekly email. Sign up today!
advertisement

Most Recent Comments

Why Did Gonzales Hackers Like European Cards So Much Better?

I am still unclear about the core point here-- why higher value of European cards. Supply and demand, yes, makes sense. But the fact that the cards were chip and pin (EMV) should make them less valuable because that demonstrably reduces the ability to use them fraudulently. Did the author mean that the chip and pin cards could be used in a country where EMV is not implemented--the US--and this mis-match make it easier to us them since the issuing banks may not have as robust anti-fraud controls as non-EMV banks because they assumed EMV would do the fraud prevention for them Read more...
Two possible reasons that I can think of and have seen in the past - 1) Cards issued by European banks when used online cross border don't usually support AVS checks. So, when a European card is used with a billing address that's in the US, an ecom merchant wouldn't necessarily know that the shipping zip code doesn't match the billing code. 2) Also, in offline chip countries the card determines whether or not a transaction is approved, not the issuer. In my experience, European issuers haven't developed the same checks on authorization requests as US issuers. So, these cards might be more valuable because they are more likely to get approved. Read more...
A smart card slot in terminals doesn't mean there is a reader or that the reader is activated. Then, activated reader or not, the U.S. processors don't have apps certified or ready to load into those terminals to accept and process smart card transactions just yet. Don't get your card(t) before the terminal (horse). Read more...
The marketplace does speak. More fraud capacity translates to higher value for the stolen data. Because nearly 100% of all US transactions are authorized online in real time, we have less fraud regardless of whether the card is Magstripe only or chip and PIn. Hence, $10 prices for US cards vs $25 for the European counterparts. Read more...
@David True. The European cards have both an EMV chip AND a mag stripe. Europeans may generally use the chip for their transactions, but the insecure stripe remains vulnerable to skimming, whether it be from a false front on an ATM or a dishonest waiter with a handheld skimmer. If their stripe is skimmed, the track data can still be cloned and used fraudulently in the United States. If European banks only detect fraud from 9-5 GMT, that might explain why American criminals prefer them over American bank issued cards, who have fraud detection in place 24x7. Read more...

StorefrontBacktalk
Our apologies. Due to legal and security copyright issues, we can't facilitate the printing of Premium Content. If you absolutely need a hard copy, please contact customer service.