Transport for London (TfL) starts on 8 July follow passenger phones in the London Underground standard. Wi-Fi access points in 260 of the capital's stations will follow customers using the MAC addresses of their phones, allowing TfL to view the routes they take over the network, as well as through individual stations as they move from platform to platform to go.
Because the system relies on MAC addresses that phones automatically send to Wi-Fi access points when they try to connect, the only way to log out of this system is to completely disable Wi-Fi. However, if Wired notes, TfL anonymises the data it collects. MAC addresses are provided with a token, which means that they are replaced by an ID that cannot be traced to a smartphone or the customer who owns it. The transport authority says it does not collect browser history or historical data from devices.
The purpose of tracking is to better understand how people use the Tube network and to provide better real-time information about traffic in stations. TfL can already use tickets to understand the stations people are on their way to, but as of later this year, employees of the London Underground will have access to public data to give people better advice on how to make their journey. TfL also plans to issue crowding alerts through its website and social media channels. Perhaps even more importantly, crowd data is also offered through the authority's existing API & # 39; s, allowing mapped companies such as Google Maps and Citymapper to adjust their recommendations for public transportation to avoid areas with high congestion.
TfL says the program will also be used to benefit its advertising space by "emphasizing the effectiveness and liability of its advertising domain based on actual customer volumes." If a large number of customers use a certain corridor in one of its stations, TfL wants that data to be given to potential advertisers.
TfL says it worked closely with the data privacy watchdog in the UK, the Information Commissioner & # 39; s Office (ICO), in the rollout of the scheme and that the MAC anonymous solution has regulatory approval. got. Signs are placed around stations, similar to existing CCTV warnings, to inform customers about the tracking program.