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Cost-efficient and reliable trains, including high-capacity trains and high-speed trains

IP Coordinator: Javier Goikoetxea - CAF


Total Project Value:
€ 6 132 399,18
from 01/12/2020 to 31/07/2023
S2R (Of H2020) co-funding:
€ 4 585 831,39
Jose Bertolin
Complementary projects:
Project website:


D1.1 Drive-by-Data Requirements Specification


D2.1 Requirements for Wireless Devices Integration Components


All deliverables, results and publications herewith provided reflects only the author's view and the S2R JU is not responsible for any use that may be made of the information it contains.

Transport of people and goods is a fundamental need for the global society and economy as it allows citizens to enjoy the freedom to travel and enables transportation of goods within and across international markets. In this context, transport is one of the fundamental pillars for the European society and economy allowing Europe to provide connectivity between its different regions and remain fully and competitively integrated with the rest of the world and the world economy. Transportation is a key infrastructure for European citizens not only to improve their every day’s quality of life, but also to enable economic growth, job creation and overall prosperity. The European railway industry evaluated how other transportation industries have addressed the development of new technologies and which architectural concepts have been applied. This led to a revaluation for the rail industry providing significant and fast progress in safety, security and in the integration of new functions.

OBJECTIVE 1: Advanced safety architecture and DbD devices in order to pass from prototypes to TRL 6/7 solutions

Challenge: To improve the deterministic behaviour in train communications, i.e.the Drive-by-Data (DbD) concept, in order to pass from prototypes to TRL 6/7 and implement it at all network levels: at backbone level, at consist level, and at end-device level. This implies modifying all the network elements that currently deploy the wired communications inside the train, namely the Ethernet Train Backbone Nodes (ETBNs), the Consist Switches (CSs), as well as the End Devices (EDs).

Proposition: Drive-by-Data devices (ETBN, CS, ED) are currently in a prototype state (TRL4/5), and they will be developed until TRL6/7. Safe4RAIL-3 will integrate the DbD concept in all these devices, prove the interoperability among implementations from different manufacturers, integrate the devices in the two CFM project demonstrators (i.e. metro and regional), and participate in the validation of the devices in these demonstrators. In order to develop the DbD devices, the expertise of railway network-device manufacturers is combined with the expertise of Time-Sensitive Network (TSN) technology suppliers and system architects.


1. Drive-by-Data devices (ETBN, CS, ED) from two different manufacturers
2. Interoperability among implementations from different manufacturers
3. Validation of the DbD concept 

OBJECTIVE 2: Advancedwireless technologies for a wireless TCMS

Challenge: the challenge is to provide TRL 6/7 devices and antennas for the CFM demonstrators. This involves providing TRL 6/7 devices for the WLTB (TCMS and OMTS traffic), WLCN (TCMS and OMTS traffic), and also antennas for both WLTB and WLCN. It also requires the identification of the most optimal locations for the antennas in each wireless domain in order to allow an optimal integration in the CFM demonstrators.

Proposition: Safe4RAIL-3 proposes the following solutions:

1.  TRL 6/7 devices for WLTB:

a. For TCMS traffic, two complementary solutions are proposed, with different technical capabilities:
i. OAI-based LTE-V2X modules. Stemming from Safe4RAIL-2 results (TRL 4-5), these ‘Beyond 4G’ modules are built on upper-layer and lower-layer modifications from the 3GPP LTE V2X/D2D rel.14 standard to support WLTB requirements. In Safe4RAIL-3, these OAI LTE-V2X modules will further be extended to reach TRL 6-7.

ii. Commercial LTE-V2X modules. To support interoperability with commercial devices and as contingency to (i), TRL 6-7 commercial LTE-V2X modules will be customized with the upper-layer functionalities developed by Safe4RAIL-2. These devices provide the required TRL, but not allowing modifications to the physical layer, they will not be fully compatible with WLTB requirements. Full functional compatibility will be achieved with OAI LTE-V2X modules (see i).

b. For OMTS traffic, IEEE 802.11ad devices are proposed, which allow a high-throughput and a stable link via self-directed mm-wave beams. These devices have been validated for T2G links and will need to be customized in Safe4RAIL-3 for inter-consist connections in the WLTB.

c. TRL 6/7 Adapted-ETBNs (AETBN) will also be provided. These devices will take as a basis the results of Safe4RAIL-2 and will advance them in order to obtain a higher-TRL solution.

d. Additionally, the possibility of a SIL-2 certification of these WLTB devices will be analysed
2. TRL 6/7 devices for WLCN: railway-certified commercial IEEE 802.11ac devices will be provided for both TCMS and OMTS traffic. Access Points (AP) as well as Ethernet bridges will be used for those end devices not having wireless functionality.

3. TRL 6/7 antennas for WLTB and WLCN: based on the output of the antenna installation study (see 4), commercial railway antennas will be selected, and their performance will be validated.

4. Antenna installation study for the CFM demonstrators: a study will be carried out covering the three communication domains of the train (i.e. WLTB, WLCN and T2G). This study will include ray-tracing simulations as well as validation measurements.


1. TRL 6/7 devices and antennas forWLTB and WLCN.

2.Validation of antenna installations based on the results of the study

OBJECTIVE 3: Integration of TCMS subsystems (AP) on Functional Distribution Framework

Challenge: Integrating SIL-4 railway functions in a Functional Distribution Framework (FDF) is an open problem because the available solutions in the market have been developed following the requirements of other domains like automotive. Mastering the trade-off between TRL 6/7 development tools suitable for railway and “off-the-shelf” solutions is the challenge for the development of TCMS subsystems in Safe4RAIL-3.

Proposition: Currently available FDF solutions are prototypes (TRL4/5) and do not yet fulfil safety requirements for the integration of SIL-4 functions. In Safe4RAIL-3, the integration of the FDF in a SIL4 CCU hardware is proposed. Guidelines for the implementation of Application Profiles, i.e. the HVAC Subsystem, for the configuration of the FDF functional modules and for the integration in the execution platform will be defined. These will be implemented in the two CFM project demonstrators.

1. Methodology to develop SIL-4 functions for the FDF
2. Application Profile integration on the FDF running on SIL-4 hardware.

OBJECTIVE 4: Assessment of the safety and cybersecurity of DbD, FDF and Wireless TCMS

Challenge: DbD, FDF and Wireless TCMS are complex systems with a novel architecture and implementation where only limited knowledge about the safety and security threats and implications is available. A rigid and systematic approach for assessment following the latest insight in safety and cybersecurity and anticipating future demands in safety functionality and security exploits has to be found. The systems have to be analysed and assessed following this approach. At the same time compliance with well-established standards and practises has to be shown.

Proposition: A team of experts in safety and cybersecurity will be brought together in common workshops to prepare the assessment approach. This team will also support the assessment work of single partners. A final compliance evaluation by a certification authority will be added as a further measure.

Exemplary safety and security analyses will be executed targeting DbD, FDF and Wireless TCMS. A common ground for the analyses will be established upfront clearly keeping them in line with state-of-the-art practise and normative requirements from IEC 62443/ TS 50701 and EN 50126/50128/50129/50657. The analyses will be reviewed by an accredited body for cybersecurity and functional safety.

Analyses reports for DbD, FDF and Wireless TCMS safety and cybersecurity and final compliance reports by the certification authority.

OBJECTIVE 5: Development of a centralization tool for the DbD
Challenge: The DbD concept is based on the scheduling for the real-time traffic as well as the configuration parameters for various devices in the system level such as ETBN, CS, and EDs. This makes the manual configuration by the user very difficult and highly risky to human errors. Therefore, a tool for such concepts is essential and important. Safe4RAIL-3 project will implement tools to be able to configure the DbD devices.

Proposition: Safe4RAIL-3 will provide configuration tools for the DbD devices. The tools will allow to configure the ETBN and CS and End Devices with the proper configuration for the real-time traffic, best effort messages and the clock synchronization parameters. In order to improve the accuracy of the tool, several approaches and models will be explored, as well as a combination of data from the use cases.

Configuration tools for the DbD 

OBJECTIVE 6: Contribution to benchmarking of proposed NG-TCMS as well as standardization in railway and wireless domains

Safe4RAIL-3 will promote and disseminate its technologies and results in international organizations to achieve a global adoption, both at standardization level and within the industry. This is a critical step in increasing the European Rail Industry competitiveness in the global markets, providing both technological leadership and market access.

The outputs of Safe4RAIL-3 will provide the results and the return on experience coming from the technology demonstrators using high-TRL devices. The main contributions will be in the following areas:

1.  The DbD network architecture will contribute to the extension of IEC 61375 standard series. This contribution will be done in close collaboration with the CFM project. In 2020, there had already been formal requests from CONNECTA-2, supported by Safe4RAIL-2, to IEC TC9 to extend the IEC 61375 standard with the inclusion of the NG TCN and DbD concepts.

2.  The results regarding the wireless train backbone will further contribute to ETSI ERM and CEPT/ITU for potential spectrum requirements and coexistence between consist-to-consist and other V2X communications, and to 3GPP TSG RAN and SA for 5G V2X specifications supporting railway use cases, as well as wireless TSN specifications supporting 5G V2X technologies.

3.   DbD activities regarding deterministic communications will also contribute to IEEE 802.1 TSN. 

1. As a result of the Safe4RAIL-3 activities, the proposed extensions to the existing railway wired & wireless standards will be refined, promoted, and drafted into the standardization committees. The circulation of documents for voting to the national committees will follow the specific standardization committee processes.
2. Active participation of consortium members in the identified standardization committees.

OBJECTIVE 7: Testing and validation of Safe4RAIL-3 devices and tools into CFM project’s demonstrator

Challenge: Integration and validation of Drive-by-Data devices (ETBN, CS, ED) with CCU/VCU provided by the complementary call for members (CFM) to prove the interoperability of TSN and FDF technologies, as well as. integration and validation of wireless TCMS devices and antennas for WLTB and WLCN.

Drive-by-Data (ETBN, CS, ED) and wireless TCMS devices are currently in a prototype state (TRL4/5) and will be developed until TRL6/7.

1. Interoperability among implementations from Safe4RAIL-3 and CFM project Drive-by-Data devices.
2. Wireless devices and antennas for WLTB and WLCN successfully integrated in the CFM demonstrators.


Results and Publications

D1.1 Drive-by-Data Requirements Specification


D2.1 Requirements for Wireless Devices Integration Components


All deliverables, results and publications herewith provided reflects only the author's view and the S2R JU is not responsible for any use that may be made of the information it contains.

This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No: 101015405