Telstra has promised Internet speeds up to six times faster will be among the benefits of two networking projects worth about $1.6 billion.

The carrier on Wednesday revealed it will improve its inter-city fibre network by adding up to 20,000km of cable, and set-up a complementary fibre network for global communications provider Viasat.

Telstra boss Andy Penn said there was demand for more fibre capacity.

The improved fibre network would help users working remotely, watching movies and gaming and other activities.

Mr Penn said this would provide speeds six times the common download rate of 100Gbps.

The upgrade would also improve connectivity for regional areas, Mr Penn said.

Parts of the inter-city network will be retired.

Work starts this financial year and take about five years.

The fibre network project makes up about two thirds of the $1.6 billion investment.

Meanwhile, Telstra will also build and manage a fibre network for Viasat as part of a 16 year contract.

Viasat provides Internet services to consumers and businesses, including in Australia, and will use three new satellites for the regions of its network.

Telstra will have satellite access node equipment at hundreds of sites and build fibre links to each.

Telstra enterprise executive David Burns said the project would be quite an engineering feat given the hundreds of points that needed to be connected.

The ground station set-up in Australia will help the satellite broadcast across the Asian region.

Staff at Viasat and Telstra have been discussing the project for the past 12 months.

Chief financial officer Vicki Brady said the projects would contribute earnings of $200 million by 2026.

The value of the Viasat contract was not disclosed.

Telstra shares on the ASX were higher by one per cent to $3.99 at 1521 AEDT.

– AAP