Tap It: How Urban Transport Ticketing Transformed Banking

Transport for London

Millions of people rely on RFID-enabled cards to travel around their local transport network, but how many of them stop to think how it works? (Image provided by TfL)

If you’re in Vancouver, you might have a Compass, or in Sydney, an Opal. San Francisco favors the Clipper, while it’s the Navigo in Paris, and the Snapper here in Wellington. But arguably, the most iconic transport smartcard in the world is London’s Oyster card. And it turns out that it’s transformed far more than the way people move through the city.

To understand how, we need to start with paper tickets. In the early days of Britain’s railways, clerks in the booking office had to laboriously complete three-part tickets for each customer – the passenger kept one slip, the office kept the second, and the third slip was handed to the guard on the train. As train travel became more popular, operators began to struggle with long queues. The lack of serial numbers on these handwritten slips also led to issues with accountability – unscrupulous clerks and guards were found to be pocketing fares. It wasn’t until the mid-1800s that a ‘standardized’, numbered ticket – the Edmondson system – was introduced to the UK, and was adopted in many other countries.

The following century saw an explosion in urban populations, and a requisite growth in the world’s railway network, but this was not accompanied by a substantial changes in the world of ticketing. Manually-operated entry gates to train stations had slowly become more common, but most public transport passengers continued to rely on bits of paper – or occasionally, metal tokens – to get around their city.

In 1950s London, this was starting to cause problems. The Tube network was bigger and busier than ever, which prompted operators to consider installing automated gates, like those in NYC. “We knew that this would help ease congestion, but it was complicated by the fact that London has always had fares based on distance,” Shashi Verma, Chief Technology Officer of Transport for London (TfL), told me, “Standard metal tokens weren’t an option.” So, the then-named London Transit Authority started looking at alternatives. The result, which was released to the world in 1964, was the printed magnetic stripe. The idea of using magnetism to store information had been around since the late 1800s, and magnetic tape was patented in 1928 by audio engineer Fritz Pfeulmer. But transport was its very first ‘real-world’ application. A full decade before the now-ubiquitous black/brown magnetic stripe was added to a single bank card, it was printed onto millions of tickets for the London Underground.

The stripe consists of carefully-aligned iron oxide particles suspended in a resin. Because these particles are ferromagnetic, they respond to external magnetic fields. By rapidly changing the current flow in a nearby ring magnet, data can be ‘written’ to the stripe as a series of 1s and 0s. Standard paper tickets used on the UK rail network have a storage capacity of 192 bits, allowing them to store information that includes the ticket type, and expiry date.

This system offered TfL the flexibility they needed in their ticketing system, and worked well for nearly twenty years. But that was partly because, during the same period, Tube passenger numbers had been steadily declining (attributed to a growth in the suburbs). As London transformed into a modern financial hub in the 1980s, the Tube began to get busier, and work patterns started to change. “By now the gates were a major point of congestion,” said Verma. “And we were dealing with enormous queues at the ticket windows.” TfL began to realize that they weren’t serving all of their customer base. “Those on monthly or annual travelcards were ok, but we had lots of regular, but not daily, customers too. They had to queue up for every single trip.” It wasn’t a good experience for anyone, really. As Verma told me, “Ticketing is not our core job – we’re there to get people to where they want to go.”

It was then that TfL started talking about smartcard technology; a small plastic card that could be used to store tickets for daily commuters, and a cash balance that could be topped up for casual users. TfL trialed the first iteration of this technology on the Tube in 1991, and on London buses in 1993. But despite the success of the trials, the scale of the changes needed to roll it out across the network were enormous, and other priorities kept reaching the top of their list. The Oyster card finally went live for customers on 30th June 2003 (Happy fifteenth birthday, Oyster!). London wasn’t the first city to use smartcards for transport – Hong Kong’s Octopus and Washington DC’s SmarTrip both predated it – but according to Verma, “…They both had relatively simple fare systems, especially compared with London.”

Since its introduction, the Oyster card has allowed people to move (relatively) seamlessly through London’s transport network, beeping them from Tube to bus to train, and back again. Like most transport cards, the Oyster achieves this using radio-frequency identification (RFID) technology. The card itself contains an integrated circuit with two main components – a tiny microchip that stores data, and an antenna that can transmit and receive data. The RFID readers – which on the Tube, are bright yellow disks found on every station gate – contain a two-way radio transceiver. When the card is brought close to the reader, the reader sends a pulse of radio waves to it. This effectively activates the chip, providing enough power for the reader to check the card’s serial number and the presence (or absence) of a ticket or pay-as-you-go balance. It is very much like a digital ticket-stamp. If Oyster users choose to register their card, TfL also collect anonymized data on their journeys. Across the entire network, this is a huge amount of information, and it is a key transport planning tool for the city. (CONTINUED…)