Victoria's regional rail network remains at standstill after Telstra outage

Victoria's regional rail network remains at a standstill following a nationwide telecommunications outage yesterday that stranded commuters.

V/Line says today's morning peak services will remain affected, with "very limited" replacement bus services operating.

The operator is advising passengers not to travel on V/Line services today if possible.

"We acknowledge this has been inconvenient to many people and thank passengers for their patience as work continues to safely restore services," a V/Line spokesperson said.

The cause of yesterday's outage was a software defect that caused time synchronisation issues across Telstra's network.

But while Telstra said the company had identified and resolved the issue by 4pm yesterday, V/Line services remained suspended overnight and into this morning.

It meant commuters were left waiting hours for replacement buses at train stations last night, with the coaches also impacted by the telecommunications outage.

The Australian Rail Track Corporation (ARTC) advised V/Line that Telstra's ongoing telecommunications reliability issues mean it is not yet safe to resume train operations.

SIM card failure led to standstill

V/Line chief executive William Tieppo said the network outage interfered with the SIM cards used on each train to communicate with the wider network.

"That's predominantly a contract that's between the Australian Rail Track Corporation and Telstra, and we obviously get that service through ARTC and Telstra," he told 774 ABC Melbourne radio yesterday.

V/Line migrated its essential train communication services to Telstra 4G in 2024, following the shutdown of the 3G network.

Mr Tieppo said V/Line was in discussions with ARTC about a longer-term backup system to address the issues arising from yesterday's outage.

"I think that's something that we'll continue to work on with our national operators and ARTC collectively," Mr Tieppo said.

"The backup system is obviously one that will be looked at at a national level, not only just for Victoria."

The ABC has contacted ARTC for comment.

Mr Tieppo said V/Line was still transitioning its systems from analog to digital, and moving from technology like copper wire to fibre and cloud-based systems.

"As the world moves to a new technology, we have to move to it; otherwise we've got assets that won't be able to function anymore," he said.

He noted the Metro Trains system used a different radio system than V/Line and thus was not affected by the outage.

Calls to make rail system more resilient

Hai Vu, a transport engineering professor at Monash University, said issues were common when there was a reliance on legacy systems.

"Over time, the system has been built on a certain technology, and then, after that, it's been incrementally updated rather than thinking from the system and design perspective to make it more resilient," Professor Vu said.

He said maintaining the regional rail network was also a challenge due to its wide geographic footprint.

"It is also an indication that the urban metro system is probably a newer system," he said.

"The coverage is probably relatively closer in terms of the scale compared to the regional system, and therefore you could potentially have other systems in place, such as cable, to actually bridge some of the web."

But Professor Vu said there was no turning back from the transition to digital tech.

"We need to be thinking about how we can make these systems more robust and more resilient, rather than saying that we shouldn't rely on them, because I think it's almost a point of no return," he said.

The Victorian government committed $1.3 billion to improving the state's rail system in May's budget, including $318 million for maintenance and safety upgrades on regional lines.