GERMANY’s national infrastructure manager, DB InfraGO, says it has analysed the cause of a GSM-R malfunction on June 23 which paralysed the network for 2h 20min. It has also introduced several countermeasures to prevent a recurrence. 

DB says that a software error occurred at 22.30 on June 23 during scheduled maintenance work to replace a switch, a network distribution component, ​​which failed to trigger an error message. To make matters worse, the redundancy of the GSM-R system failed to activate automatically, even though it was fully functional.

This resulted in all trains being held at stations. At 00.03, DB started to issue passengers with taxi and hotel vouchers.

After staff had ruled out a cyberattack, the system was manually switched to the fallback situation after about 90 minutes, and by 00.50 the problem had been fixed and services started to resume.

“The GSM-R digital train radio system is normally completely reliable, which is why all other railways in Europe use it as standard,” DB InfraGO says. “For safety, the train radio system is built with redundancy, meaning there is a backup system that automatically switches to in case of malfunctions.”

Response

DB InfraGO has implemented three countermeasures to prevent the disruption from recurring: 

  • component replacement has been put on hold for now
  • troubleshooting of the affected component is underway in cooperation with the manufacturer, and
  • maintenance work will in future only take place between midnight and 04.00 and only in the inactive redundancy situation.

In addition, DB will issue a report to regulatory authorities on the event to the German regulator.

DB InfraGO CEO Philipp Nagl says the infrastructure manager is currently undertaking a comprehensive overhaul of the existing GSM-R network and is reorganising the fallback system via the public mobile network. “We deliberately decided on these two measures some time ago to address past investment backlogs and to lay the foundation for the further rollout of ETCS,” he says.

DB InfraGO says GSM-R will remain in use in Germany for at least the next 10 years and there is currently no alternative. Although it is a lead participant in the project to introduce the new Future Railway Mobile Communication System (FRMCS), which will replace GSM-R in the long-term.

“As part of the corridor upgrade, the Hamburg - Berlin line has already been equipped with fibre optic cables and masts in order to equip the first main line for trial operation as soon as possible,” Nagl says. “However, FRMCS has not yet been specified by the European Union. Therefore, components for it cannot yet be ordered and installed.”