Telstra is to spend $250 million upgrading the resiliency of its networks in the wake of a series of outages that have tarnished its carefully-crafted image of reliability.

CEO Andy Penn said the company would take the quarter of a billion dollars from within its “existing capital program” and redirect it into resiliency projects across its core, fixed and mobile networks.

It includes an already announced $50 million investment that Telstra announced in May to fix problems in its mobile network that led to three major outages.

Two of those mobile outages saw Telstra offer its customers a day of free data as compensation.

Customers collectively downloaded thousands of terabytes of mobile data on each day, testing the limits of the most data downloaded over the network in a single day.

Since then, however, the telco has been struck by a series of failures in various parts of its fixed line network.

The latest outage lasted seven hours for business fibre customers and came just a day after Telstra revealed its $250 million investment plans.

Penn said the telco is doing everything it can to strengthen its network against disruptions.

“All network operators around the world face the risk of disruptions,” he said.

“What I am committed to though is continuing to invest in building the durability and capability of our network, and in our ability to respond quickly if things do go wrong to minimise the impact on customers.”

Penn apologised again to customers that had been affected by the outages.

The outages have been particularly damaging to Telstra as the telco has for a long time traded on the reliability, uptime and technical stability of its networks.

Rival Vodafone suffered its own network performance issues back in 2011, culminating in a user-led campaign dubbed Vodafail to highlight the problems.

It spent billions to revamp its network and turn its fortunes around.