Spark plans to retire PSTN in Devonport and Miramar by Christmas. The move will affect around 1000 customers.

It is the latest step in Spark’s plan to move customers from copper on to either fixed wireless connections or fibre.

PSTN is the public switched telephone network: the old copper-based telephone system.

Spark says PSTN is now at the end of its life and needs replacing. It is now 17 years since equipment makers stopped making PSTN hardware. Spark says it is getting harder to find people with the skills to maintain the technology.

It is possible to deliver services resembling PSTN voice calling on fixed wireless and fibre connections. Yet the alternatives do not work in a power outage.

This may confuse older, reluctant to switch customers, but there are workarounds.

There are difficulties with security or medical alarms designed for copper network technology. Spark says it will not move anyone who needs special hardware until it has found a replacement.

A move from copper networks may have been controversial a few years ago. Today the majority of customers in cities and towns now use fibre or fixed wireless instead.

Fibre uptake is now 60 percent or better in urban areas. There are 180,000 homes or businesses using fixed wireless connections. Meanwhile there are more mobile phones in use than there are people.

Spark is moving early. Later this year new Telecommunications Act provisions will come into force. These allow Chorus to stop offering copper services where fibre is available.

Chorus continues to own and operate the copper networks. They will remain in the ground for now even in the areas where Spark has withdrawn services.

By running pilot programmes in Devonport and Miramar Spark will be able to better understand how decommissioning PSTN might work. The company expects to spend years moving off the services across the rest of the country.