News from BWCS

TfL Starts Monitoring Tube Passengers Via WiFi Data

Wed 10 Jul 2019

Transport for London (TfL) has begun tracking travellers’ movements across the Undergound network, based on the data-trail left as they hop from WiFi-point to WiFi-point. As passengers pass along the tube’s free WiFi network, TfL will access GPS data on their smart-phones in order to help monitor how busy different parts of the network are getting.

First announced in May, the move aims to garner data from more than 260 WiFi-enabled London Underground stations in a bid to understand how people navigate the tube system.  

According to Lauren Sager Weinstein, chief data officer at TfL, speaking to Railway Technology Magazine, “The benefits this new depersonalised dataset could unlock across our network - from providing customers with better alerts about overcrowding to helping station staff have a better understanding of the network in near-real time - are enormous.”

However, TfL was at pains to point out that it takes its customers’ privacy “extremely seriously” and, it says, it will not identify individuals from the WiFi data collected. In response to concerns raised over privacy, TfL has pointed out that passengers can opt out or switch off their devices whilst travelling. It also claimed the data will be de-personalised and stored securely. TfL has even put up signs across the network warning about the process and seeking to reassure passengers.

London currently lags behind other major metro systems in terms of on-train WiFi or even mobile connectivity. Barcelona, Hong Kong, Melbourne, Rome and Tokyo all boast either in-tunnel WiFi, mobile or both. WiFi and mobile links have both been available on the Moscow Metro since 2014. Meanwhile, Seoul in South Korea seems to be leading the way with trials of pseudo 5G in its underground system.

The UK’s capital city faces several significant hurdles in the race to put WiFi, or at least 4G, connections onto its tube-trains. The sheer expense and difficulty of running new cables around the often narrow, ancient and curving tube system is not be under-estimated. TfL believes that the network would need to be capable of carrying around 1 terabyte per day.

Most experts believe that an enormous number of access points would be needed to generate acceptable levels of coverage on the London Underground network. In addition to the heavy cost of equipment, maintenance would also be difficult and expensive in the cramped tunnels.

Two years ago, TfL conducted a pilot scheme which saw it install fibre and 4G technology in the tunnels running between Bank and Waterloo Underground stations, on the Waterloo and City Line.

The four major UK mobile network operators Vodafone, O2, Three and EE all took part in the trial. According to TfL the trial also gave engineers the opportunity to practise laying new fibre cables within stations and tunnels.

Speaking at the time, Graeme Craig, Director of Commercial Development at TfL, said, “The success of this trial shows that we are on track to unlock one of the UK’s most high profile not-spots and deliver 4G mobile coverage throughout our tunnels and Tube stations.” The trial, which took place during engineering hours and was deemed a success, culminated in a test journey being made from one end of the line to the other with uninterrupted data coverage.

By early next year, some lines in central London may be offering 4G connectivity for voice signals. However, directly accessing 4G data services means that the transport operator will not be able to choke off the signal of any users who are streaming video content to the detriment of other on-board connections.

On-train WiFi services, trackside networks, the growing market for passenger WiFi and on-board entertainment were the main subjects of BWCS’s recent WiFi on Trains Conference 2019 on the 4th and 5th of June.

For more information on the conference please see and for more detailed country-by-country data on how the market for on-train WiFi services is developing please see or contact

The 2019 conference ( ) was sponsored by Icomera, Nomad Digital, Fluidmesh, RADWIN and BAI Communications. For information on the 2020 event, please contact