THE PAST

Rail: A pioneer of digital technologies

‘Digital’ – in its purest meaning, means a system which performs logic in terms of two states – ‘on’ and ‘off’, or ‘1’ and ‘0’. Data is sequences or streams of these logical states.

The railway, therefore, was a trendsetter! Long before ChatGPT, 5G smartphones, e-tickets, digital TV or indeed even the humble monochrome VDU, and whilst we were still burning coal for traction during the Victorian era, our signalling systems were using digital techniques in cutting edge train and points detection to keep our passengers safe. The design of ever more complex interlockings, which are a digital state machine (though not a true computer in the Turing machine 9 sense) became a science. People, beyond of course those with more than a passing interest in rail technology, were probably none the wiser as to the ‘digital’ techniques in use behind the scenes.

The development of true – i.e. reprogrammable –computer technology during the 1950s and ’60s eventually led to the word ‘digital’ becoming more widely used in society to mean ‘computing’10 . Through this period UK railways remained at the cutting edge operationally. TOPS (Total Operations Processing System), for example, is a very early example of a digital business system rolled out nationally as ‘a single source of truth’ in the late 1960s. SSI (Solid State Interlocking), developed in the 1970s and ’80s took the latest computing techniques and developed them for application to safety critical infrastructure. SSI is programmed with a dataset representing a logical decision map – a true Turing machine. SSI was a success at home, and a popular export, remaining in use worldwide.

More recently, the rollout of in-cab signalling – ERTMS (European Rail Traffic Management System) and ETCS (European Train Control System) – has been re-branded the ‘digital railway’, to properly capture what the initiative is trying to achieve in the hearts and minds of the public, whilst dropping some of the jargon that is pervasive to our industry. Digital, in this sense, mainly refers to the digital communication technologies upon which such techniques are based, digitally transmitting the correct data to the cab for the direct interpretation of the driver.

Signalling generally doesn’t require a lot of processing power, but decisions need to be guaranteed correct for safe operation, so it presents some unique challenges. In theory the safety critical signalling processing for the whole UK network could run on a single average ninth generation video game console of the late 2020s, costing around £400. In the same vein, the Apollo guidance computer used in the ’60s and ’70s moon landings could run on an average ’80s pocket calculator. This rapid advance in processing power, the corresponding reduction in its cost and increase in its portability, is broadly governed by Moore’s law3 , which predicts that the computing power available on a microchip doubles every 2 years.

The impacts of Moore’s Law led to the widespread societal changes which we have witnessed since the adoption of IT in the ’70s and ’80s. It will continue to change society for the foreseeable future, with no signs of slowing down. This growth of computing power makes technology from each decade almost unrecognisable from the last. Most importantly, it has three main effects on the railway, and its customers:

• The list of ‘things we can do’ is ever growing, and there is no single source of truth about our current capabilities.

The list of ‘things we could do’ is growing more rapidly; and we will never know every item on this list.

• The expectations of our customers around what we can and could do are growing the quickest of all, and future projections of these present the greatest unknowns.

Taking the first point: in recent years our industry has deployed data and digital technologies at a rate never seen before. Examples of both customer-facing (e.g., e-ticketing, delay information, communications) and back-office (e.g., remote condition monitoring, live timetables in disruption) are plentiful and some are featured in the case studies section at the back of this document.

However, every deployed technology, and every advance in computing, opens many more opportunities than it is possible to list – the evergrowing list of things that we could do. The items on this list aren’t all in one place – they span organisations, disciplines, and the client/supplier interface. No one entity knows – or will ever know – all the things we

Data and Digital: Definitions

Data (noun)

1. a plural of datum.

2. individual facts, statistics, or items of information.

3. information in digital format, as encoded text or numbers, or multimedia images, audio, or video.

4. a body of facts; information:

Digital (adjective)

1. displaying a readout in numerical digits rather than by a pointer or hands on a dial.

2. of, relating to, or using numerical calculations.

3. of, relating to, or using data in the form of numerical digits.

4. involving or using numerical digits expressed in a scale of notation, usually in the binary system, to represent discretely all variables occurring in a problem.

5. available in electronic form; readable and manipulable by computer.

Source: www.dictionary.com could do, not least because this requires knowledge of what data sources are accessible and sharable. Sharing an outline of what data exists in each organisation, if not the data itself, therefore forms part of one of our asks. The outcome of such an exercise would indicate what outcomes are achievable, versus those which are desired.

Finally, this brings us to the expectations of our customers – both passenger and freight. These are already changing immeasurably based on what could be achieved. We have no crystal ball – the future customer expectations and aspirations for rail are impossible to predict. We can, however, look outside the railway to see how changing usage patterns, based on digital ubiquity, have caused wholesale shifts in other industries. Later, in ‘The Future’ section, we will have a ‘Tomorrow’s World’ moment emphasising the opportunities on offer: RIA’s digital railway of the future. But first, let us examine where we are today –within and outside the railway.