Australia's massive bushfires are taking their toll on telecom infrastructure, setting off debates about how to build networks for a fire-prone future.

The fires, which have so far burnt out 17 million hectares (42 million acres), have taken out dozens of mobile masts and other equipment, cutting off communities and hampering rescue and fire-fighting efforts.

At the fires' peak on January 4-5, more than 100 basestations in the three bushfire-affected states were out of action, according to communications minister Paul Fletcher. A week later, 30 had still not been restored.

Telcos have deployed interim services through "cell on wheels" units or satellite. Telstra is offering residents free WiFi via WiFi-enabled payphones.

In a blog this week, Fletcher, a former Optus executive, says the biggest cause of outages had been the loss of mains power supply rather than the destruction of the equipment. Most had backup power sources but these lasted only a limited time.

But he said the physical resilience of future networks had become a big issue for operators.

The country's second-largest operator, Optus, said that of the 17 basestations out of action in early January, seven had been damaged by fire and would require a full or partial rebuild. Vodafone said it had lost 19 basestations, of which six had been restored by January 9. Telstra declined to issue details.

Optus CEO Allen Lew said the Sydney-Melbourne trunk fibers that ran through some of the impacted areas were still operational.

Fletcher said the full extent of the physical damage to basestations, exchanges, transmission lines and other facilities was still unclear. "If we are to face longer and more intense bushfire seasons in the future, are there designs which would better protect networks against damage?" he wrote.

He said he'd spoken to the operator CEOs and called on them to consider these issues as they plan their network rebuilds.

Fletcher says the other issue for the industry was redundancy, noting that for many consumers this meant access to a mobile as well as a fixed-line service. "Our government is concerned that there are still too many smaller towns and communities in regional and remote Australia without mobile coverage."

However, the bushfires have led to calls to retain the legacy copper access network. The mobile outages meant residents in fire-threatened areas had to rely on their old landline service, which works even if the household has no power.

But the copper local loop is being progressively decommissioned, replaced by the locally powered National Broadband Network (NBN).

The National Council for Fire and Emergency Services told the Australian Broadcasting Corp. they'd been warning for the past two years about the NBN's vulnerability in a disaster.

Telecoms analyst Paul Budde says the country needs a national emergency communications plan to deal with future disasters. For example, mobile phone towers had backup power for just ten hours, but in major fires, "it's not ten hours, it's ten days," he said. "People can't get into the area any more."

— Robert Clark, contributing editor, special to Light Reading