All mobile phones logged into the Wi-Fi network at Helsinki Airport will be monitored by an in-house tracking system that identifies passengers’ real-time movements.

The technology has been criticised by privacy advocate groups, but is said to be aimed at monitoring crowds and preventing bottlenecking at the airport, which sees around 15 million passengers a year, Bloomberg reports.

About 150 white boxes, each the size of a wireless internet router, have been placed at various points around the airport. Equipped with tracking technology from the Finland-based retail analytics company Walkbase, each device is designed to collect the “unique identifier numbers” of all mobile phones which have Wi-Fi access switched on.

Passengers can also "opt-in" for other services, by logging into the network via an application such as an airline app or retail store app, to receive sales offers from the airport’s 35 shops and 32 restaurants and cafes, in addition to any relevant flight information. Users wanting access to the WiFi network will be notified of the monitoring system before they log in to the network.

Currently at its initial phase, the full tracking system is expected to be in place by the end of this year which could enable shops to specifically target passengers that are within their vicinities, such as a deli that could alert a passenger walking by of a certain item on sale.

All data collected is said to be in aggregated form, preventing any personal information from being seen by Finavia Oyi, the Finnish Civil Aviation Administration operating the airport, as the software discards any unique identifiers of devices, claims Tuomas Wuoti, the CEO at Walkbase.

But software security analysts find it hard to believe “location tracking is only left at statistics” levels.

“The fact that my movements are tracked is a scarier thought than someone knowing which websites I visit,” Antti Tikkanen, director of security response at the software maker F-Secure Oyj (FSC1V), told Bloomberg.

The technology was also met with concern from customers at the US-based department store retailer Nordstrom where it was tested last year, who criticised it for monitoring unwary customers.

Passenger privacy concerns are “extremely important” to the group and “the anonymous monitoring respects customers’ privacy”, according to Heikki Koski, vice president of new services at Finavia Oyi.

“We’re looking at great paybacks from this investment”, he told Bloomberg, adding “We can manage the airport better, we can predict where bottlenecks might come and analyse everything more thoroughly.”

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