MAC address

Two 'MAC address' stories June 2014 - March 2015

Anonymously tracking phones through airport security cuts waiting time by a third

Cincinnati/Northern Kentucky International Airport says that anonymously tracking smartphones through airport security has enabled it to cut the average waiting time by a third.

The system, developed by Danish company Blip Systems, scans both WiFi and Bluetooth connections to look for MAC addresses of mobile devices passing through security. Counting the number of devices in each queue enables the system to estimate the length of the queue. The queue length is displayed to passengers in minutes, so they can choose which queue to join, and also used to help the airport allocate the right number of security personnel.

Blip says that it anonymizes this data, and only uses device counts. You might think iOS 8 users don’t have to take the company’s word for it since Apple introduced MAC address spoofing when scanning for networks, but the protection offered by this was last year shown to be rather limited.

The same system is used in a number of other airports around the world, but this is the first time it’s been used in the USA.

iOS 8 randomizes MAC address while scanning WiFi, blocks marketers tracking you

One iOS 8 feature Apple hasn’t talked about much is its ability to randomize the device’s MAC address while scanning for WiFi networks.

In iOS 8, Wi-Fi scanning behavior has changed to use random,locally administered MAC addresses… The MAC address used for Wi-Fi scans may not always be the devices real (universal) address… Once the iOS device is done scanning it will give the real MAC ID.

This appears to be a security and privacy precaution as marketing and analytics companies routinely use this unique identifier to collect data about nearby devices scanning for WiFi networks. The New York Times published a story last year about a similar experiment at Nordstrom and several marketing companies selling data to retailers and more use the same method of picking up the MAC address from devices scanning for WiFi networks. One of those companies, Euclid Analytics, explains how it currently uses the MAC address of iPhones to help clients. While it notes “the MAC address does not disclose the device owner’s real-world identity nor any other personal data,” it also uses the data it collects to help clients “improve store layouts, determine timing for promotions and sales, measure the effects of advertising, and set staffing levels and store hours.”

These marketing companies do the same for Samsung and Android devices, which also do not currently automatically randomize the MAC address, but it looks like Apple might put an end to that with iOS 8.