Deutsche Bahn suspended all train services across Germany late on Tuesday after a nationwide failure of its GSM-R digital railway communication system forced trains to be held at stations. The state-owned operator said the outage affected the GSM-R network, which provides voice and data links between train drivers and control centres and is used for internal communication across the railway.

Deutsche Bahn CEO Evelyn Palla told Bild that the company had not yet identified the cause of the disruption [Source: Reuters]. A spokesman separately said technicians were working to resolve the problem and that further information would be provided as soon as possible [Source: Reuters]. In a statement issued around midnight — approximately an hour and a half after first announcing the problem — Deutsche Bahn said the cause had been identified but did not specify what it was [Source: Associated Press].

Passengers were left stranded at stations across the country during the outage. Deutsche Bahn said it would provide taxi and hotel vouchers to affected travellers and, where possible, make stationary trains available for passengers to sit in. About two hours after the outage was first reported, trains on at least part of the network were moving again. The Berlin commuter network confirmed services had resumed but warned that delays and cancellations should still be expected. DB Regio Mitte, which operates regional trains in parts of western and southwestern Germany, said it had also resumed service but cautioned that disruptions should be expected to continue until at least 6 a.m. on Wednesday.

GSM-R — short for Global System for Mobile Communications–Railway — has been rolled out across Europe as a common standard for railway operations since 2000, according to the European Union Agency for Railways [Source: Associated Press]. The system underpins the safety-critical communications that allow trains to operate on a shared network. Deutsche Bahn is fully owned by the German federal government and carries no publicly listed equity.

Tuesday's incident adds to a pattern of service reliability concerns at the operator. Complaints about train delays and disruption in Germany have become increasingly frequent in recent years, and Deutsche Bahn has been conducting thorough overhauls of major routes following a prolonged period of underinvestment in the network. Those overhauls have themselves caused significant disruption to passengers.

Sources: BBC News, Bloomberg, Sky News, Associated Press, Reuters