Interviews

Laying the foundation for a digital railway

Craig Ellis, Network Rail Telecoms head of technology & engineering, talks about the development and deployment of the FTNx network and the future benefits it will deliver. David Stevenson reports.

Network Rail has gone live with its new FTNx telecoms network, with the ultimate aim of delivering a safe and secure Digital Railway for the future.

 Most of the nodes were completed and switched on in October 2014 during phase one of the project – as had been planned.

 Phase two of the scheme, based around enhancements, is expected to be complete by March 2015. Craig Ellis, head of technology & engineering at Network Rail Telecoms (NRT), said: “In the six months between March and October we went through the ‘activation’ phase.

 “The installations were all completed, physically, in around June and July, and from then onwards we installed all the highly sensitive optical equipment, connecting the fibres and connecting the IP/MPLS equipment.”

 MPLS stands for multiprotocol label switching, and is a way of speeding up network traffic flow and making it easier to manage, compared to traditional IP (internet protocol) routing.

 Back-end challenges

 Ellis noted that Network Rail has built an optical network and an IP/MPLS network. “The Infinera optical network, the Layer 1 network with the DTN-X platform, runs over our fibres,” he said. “In parallel the Cisco IP/MPLS network then sits on top as a Layer 3 network and all of the IP/MPLS traffic in the core gets transported over the optical layer.”

 The diagram explains Network Rail’s various lower Layers for its telecoms network. Layer 2 includes non-operational rail and passenger services, such as wi-fi on trains, while Layer 3 is about exploiting the network to deliver services off the rail corridor. Layer 4 is wholesale and enterprise fixed services off the corridor, such as rural broadband or corporate backhaul.

 NRT’s deployment of the DTN-X platform, featuring the industry’s only commercially available 500 gigabit per second (Gb/s) super-channel solution, is designed to support future terabit super-channels without requiring new chassis.

 During the DTN-X platform deployment, across more than 4,000km of fibre optic cable, NRT has made a number of changes to parameters and configurations to connect the system up at the back end.

 “This has not just been a project about the front-end equipment,” said Ellis. “There has been a lot of work on the back end, including the NMS (Network Management Systems), security firewalls, OSS (Operational Support System) and improved BMS (Building Management System), which is where some of the benefits of FTNx will arise for Network Rail.”

 Asked how this new network differs from what was in place before, Ellis told us: “The main difference this time around, deploying FTNx, has mainly been around the Network Capacity, NMS, OSS and the security aspect.

 “When FTN/GSM-R was designed and built 10 years ago, the world of network management systems was quite basic, and security was not prevalent, especially as the network was based on SDH technology [synchronous digital hierarchy, a standard technology for synchronous data transmission on optical media].

“We are now going into more of an IP/MPLS world and one of the main criteria we set out was the security aspect, and the network management.”

 NRT has been setting up geo-redundant NMS. “So, if we were to lose our primary datacentre, which is where one of the management systems is held, we have a live-live environment [a term from disaster recovery, where services run in parallel and can be ‘cut across’ nearly instantaneously], which can take over in the secondary location,” said Ellis. “It means we can access the network, configure the network and provide protection from another site. That has been a challenge and move into a new world for Network Rail.”

 Ellis, who joined NRT in 2012, added that understanding cyber-security and NMS and the way they correlate with some of Network Rail’s existing applications and devices has been a learning curve. But he added that the UK is one of only a few countries deploying an IP/MPLS railway network.

 IP/MPLS network

 With railway telecoms networks migrating towards digital transmission technologies, the adoption of unified IP-based fixed networks has become a key consideration for infrastructure managers.

 Although IP/MPLS networks across railways globally are quite early in their development, REFER Telecom – the telecoms subsidiary of Portuguese railway infrastructure manager REFER E.P.E – deployed an IP/MPLS network some years ago. Since 2001 it has operated a fixed IP communications network to support the railways operational applications. The primary objective was the replacement of legacy SDH-based TDM networks and legacy copper links. However, the benefits extend to other areas of operation.

 Other European railways are also starting out on the IP/MPLS path, and Ellis said: “Before this main project, the FTNx core, we had started to develop IP/MPLS working with Cisco up in Scotland on the Edinburgh-Glasgow project (EGIP). On EGIP we deployed, in October 2013, a smaller version of FTNx. That was a 22-node access network, which will connect into the FTNx core.”

 Ellis added that optical platforms are now transporting CCTV and critical data services for many industries around the world.

 “For Network Rail, the FTNx network has come about through product innovation happening in the telecoms industry and the demise of SDH technology, which was implemented for FTN, with vendors moving towards the end of that technology. In the next three to five years, there will be a very limited number of people who will actually be selling either SDH or PDH (plesiochronous digital hierarchy) products. It has been led by the industry and the market and a need to enable a Digital Railway.”

 Digital Railway foundation

 Ellis added that the great thing about deploying FTNx is that NRT has “laid down the foundation for a Digital Railway”.

 FTNx gives Network Rail a network capable of transporting data-hungry services, such as CCTV, Traffic Management and SCADA.

 “In a very simplistic way we are the telecoms postman for Network Rail,” said Ellis. “We need to take a data parcel from point A and deliver it to point B. These digitised services require a greater level of resiliency and redundancy, and security becomes absolutely critical.”

 The Digital Railway initiative is being driven from the top by CEO Mark Carne, and Network Rail plans to spend the next 15 years dramatically speeding up the digital enablement of Britain’s railways.

 The ambitious agenda focuses on signalling and telecoms, and Carne wants to speed up the implementation of ETCS in-cab signalling and train control, knocking decades off the original 50-year timeline.

Ellis added that one of Carne’s big drives is for safety and business performance to go hand-in-hand.

 “FTNx will enable the remote configuration and remote provisioning of services,” he said. “Traditionally, Network Rail sends engineers to the trackside with cards and terminals to configure; instead, all the configuration and provisioning for FTNx will be done remotely from the secure Network Management Centres.

 “That will really drive benefits as we move people away from the trackside, allowing us to change and configure the provision of services in hours rather than days or weeks as in the past.

 “The FTNx network also provides a solution that is highly reliable through its use of IP/MPLS, photonic integrated circuits, and the software-driven management system enables remote diagnostics and turn up of bandwidth. This is ideal for this type of network, keeping our people safe yet allowing our networks to grow.”

 Enhanced capacity

 As well as being able to configure services remotely, Network Rail now has the ability to operate in terabytes whereas in the past capacity has been restricted. “For example, on a single fibre we now have the capability to configure 80 x 100Gb/s circuits within that fibre pair, which is truly outstanding,” said Ellis.

 NRT’s deployment features Infinera’s unique Instant Bandwidth technology, which enables NRT to deploy capacity with the click of a mouse, to rapidly meet its customer service demands for high capacity, low latency services.

 Ellis added: “Within 10 minutes, we would be able to turn up a new 10 gigabit or 100 gigabit service as and when required. The previous technology, installed for FTN was the right technology at the time – SDH – but it uses timing and brings restrictions to capacity.

 “However, DWDM (dense wavelength division multiplexing) technology, which has been around for about 20 years but only came into the mass market around 2005, changes the capacity landscape.

 “Without DWDM technology you would never have had the growth of YouTube or social media, the internet would have, basically, stifled on capacity. The fundamental change is this: SDH can give you up to 10 gigabit link over a fibre, but optical technology with DWDM allows you to go from 10 gigabit to the ability to having eight terabytes across a single fibre. It is a fundamental change, and the spectrum of capacity is enormous now.”

Workforce challenge

 Is the workforce ready for the challenges of a Digital Railway?

 NRT, Network Rail’s national telecoms asset management and service provision function, has grown quickly in the three-and-a half years since its inception.

 “We will be up to around 500 people by the end of this year, and we have expanded into new skillsets, such as network architects, network designers and a dedicated security team,” he said. “There has been major growth inside NRT, and we’re also now heavily engaged with the graduate and apprenticeship schemes at Network Rail. Previously, signalling and maintenance were normally the areas of choice for graduates and apprentices but, in the last couple of years, we have seen a change.”

 But Ellis is concerned that there is a skills gap in the wider industry, especially around cyber security, network systems and IT. “I would like to see how the big players – Babcock, Mott MacDonald, Carillion, Atkins, and so on – can work together, as an industry, to align resources where they are needed going forward.”

 Pay as you grow

 RTM was told that Network Rail has initially procured a 100 gigabit link for its optical network, but “as we go on the journey in the next five to 10 years – as we introduce next-generation CCTV and develop into a Digital Railway – we will be able to purchase software keys from Infinera and switch on additional 100 gigabit capacities as we grow”.

 “With Infinera and Cisco technology it is a very cost-effective ‘pay as you grow’ platform, tailored to what you need,” said Ellis. “We needed to install a network that wouldn’t need to be overhauled in five years, and would allow us to grow as the railway goes on its digitised journey. That’s what we’ve done.”

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