Project to track phones yields wealth of data
TRANSPORT for London ( TfL) provides wifi at almost all underground stations and has just published a very interesting report.
This reviewed its pilot project to collect and analyse connections made to 1,070 wifi access points at 54 stations.
From the MAC addresses which identify each phone uniquely, they were able to track movements of phones, and therefore the passengers carrying them, through the network.
This gave them a wealth of data, from more than 500 million wifi connections made from 5.6 million devices.
Tracking a phone from each access point to the next told them what routes passengers took through each station and what connections they took between starting points and destinations.
Given that a high proportion of passengers carry phones which are switched on, and because these connect to access points whether they are in use or not, the results gave a better picture of how many people were in every part of the network, at different times of the day, than ever before.
The consequence, TfL says, will be better informed investment decisions and planning for the benefit of customer safety and congestion reduction.
They see improved customer information as well, suggesting the future development of an app for advising travellers which trains are likely to be less crowded.
There were, though, some surprises.
For instance, one graphic in the report set out the proportion of journeys taking each of 18 different optional routes between Waterloo and Kings Cross.
Although why 1.3 per cent of such passengers would change trains three times and 1.5 per cent do so twice, when the majority chose one of twelve possible routes with just a single connection, looks to be a mind- boggling mystery that defies solution.