Spark to scrap PSTN, replace with IP network

Spark has unveiled a five-year plan to scrap its aging circuit-switched public telephone network and replace it with IP technology.

The new network will underpin fixed and mobile voice services, video services and what Spark calls ‘data based’ communications.

Spark says the current network comprising 482 telephone exchanges and two nodes supporting intelligent network services provided over the PSTN is becoming difficult to maintain because equipment is longer manufactured, spare parts are hard to obtain and the skills needed are becoming scarce.

These 482 exchanges and the IN nodes will be replaced with just three network nodes — two in the North Island and one in the South Island — to provide redundancy. These will deliver a wide range of IP based voice and data services including voice over WiFi, voice over LTE, videoconferencing and collaboration.

Spark says the changeover will cause minimal disruption and most customer devices will continue to operate on the new network, although some old Sky decoders, EFTPOS terminals and PABX systems may not be compatible.

Spark’s chief operating officer, Mark Beder, described the move as “a significant and essential upgrade of our oldest network” that would provide the company with a futureproof platform for the latest voice technology, and allow it to develop and deploy new services.”

“We’ve been talking about doing this for over a decade now, and many other countries are also in the process of retiring their PSTNs, so it’s great to finally be able to get on with it here,” he said.

He added that usage of the fixed line, circuit-switched telephony was decreasing as customers favoured newer alternatives. “Already, around 50 percent of New Zealand homes and businesses are using other technologies like voice over fibre, voice over wireless, using their mobile for voice communications or relying on messaging applications.”

Spark says PSTN traffic fell to less than 50 percent of total voice traffic in early 2016.

The upgrade will be undertaken in three phases. Phase one between now and 2018 will see a new core network built with two of the planned three nodes and existing exchanges being decommissioned. A replacement for the current intelligent network, supported by nodes in Auckland and Palmerston, will also be deployed.

In phase two to 2019 migration of PSTN, wireless broadband and VoIP services onto the new platform will ramp up. In phase three, all communications will be migrated to the new network and new services enabled by it will be introduced and the third node of the new network will be deployed.

Spark said “The new network will also use virtualisation technology to enable it to scale more rapidly, and will consume much less power than the current network.”

This is a reference to network functions virtualisation – a growing movement among network operators to replace hardware dedicated to specific network functions with software running on standard processors in a virtualised environment.

Such an architecture – which also embraces virtualised customer premises equipment – enables new services to be ramped up quickly and resources to be rapidly deployed to meet demand peaks.