New Zealand telecommunications provider Spark has announced that it will be progressively upgrading its legacy copper Public Switched Telephone Network (PSTN) to an IP-based network it has named the Converged Communications Network (CCN) over the next five years.
The CCN will replace the PSTN to deliver new voice calling, landline, fibre, data, video conferencing, content, mobile, and Wi-Fi services enabling voice over LTE, voice over Wi-Fi, and voice over IP (VoIP), Spark said.
As announced in February, Spark is working with Ericsson to build the IP Multimedia Subsystem (IMS), which it has now revealed will form the core technology for the CCN.
"This is a significant and essential upgrade of our oldest network, providing us with a future-proof platform for the latest voice technology and allowing us to develop and deploy new services," said Spark COO Mark Beder.
"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."
The CCN will consist of three redundant core network nodes spread geographically across the nation, in order to ensure resilience during natural disasters or other outages.
The virtualised platform will "scale more quickly and efficiently", Spark said, with the telco able to route traffic through optical and Ethernet transport networks.
Spark plans to build the core network foundation, begin migrating and decommissioning exchanges, and introduce the IMS during 2017 and 2018. In 2019, it is aiming to scale up migrations of PSTN, wireless broadband, and VoIP; enhance calling features; and commence regional migrations.
By 2020, it is looking to have the CCN fully replace PSTN services; introduce new calling features, products, and converged services; and add the third core.
According to Spark, consumers are already moving away from the copper-based service, with around 50 percent of all premises across the country using voice over fibre, voice over wireless, and mobile services instead.
Spark has said its upgrade will only have "minimal disruption" to consumers' services, with outages of just "a few minutes" to occur during residential off-peak times between 9am and 2pm.
Out of the 482 PSTN exchanges needing to be decommissioned, Spark has already decommissioned 10 remote exchanges servicing around 3,000 customers in Nightcaps, Southland; Runanga, West Coast; Waitati, Otago; Parawera, Waikato; Masterton, Wairarapa; Te Kaha, Bay of Plenty; Kaitangata, Otago; Blenheim, Marlborough; Granity, West Coast; and Ngarua, Tasman.
Spark experienced four issues during the decommissioning of these exchanges, which were all related to old dial-up EFTPOS machines. High-risk customers, including those with medical alarms, will be monitored during any decommissioning, Spark said.
Four more exchanges are due to be decommissioned this month, in Little River and Governors Bay, Canterbury; and Paroa and Karamea, West Coast.
Spark had in February announced signing a multi-year deal with Ericsson to upgrade its voice network to be fully digital during a phased upgrade program.
The IMS upgrade will modernise and unify Spark's core networks to allow for greater reliablity and scalability, according to the telco, towards an increasing uptake of VoIP usage over both fixed-line and wireless broadband as the number of wireless and fibre connections grows across the country.
"Implementation of our next-generation core network technology with Ericsson virtualised IMS, Ericsson Cloud Execution Environment, and Ericsson Cloud Manager will provide Spark with the ability to efficiently introduce higher-quality voice and enriched communication services," Ericsson ANZ head Emilio Romeo said in February.
"Other features the teams will be working to deliver for the future are voice and video calling over LTE and Wi-Fi calling, providing Spark customers with seamless voice services coverage when moving between different accesses."
Virtualisation is also a step towards network slicing, Ericsson said, which is used with 5G for more personalisation across networks. Using the slicing technology, a physical network can be segmented into several virtual mobile networks.
Ericsson demonstrated 5G network slicing technology in partnership with South Korean telecommunications giant SK Telecom in October 2015, performing the demonstration at its R&D centre.
Spark first mapped out its network virtualisation plans back in 2015, when it told investors it would utilise software-defined networking (SDN) and network function virtualisation (NFV), saying that the use of networking software rather than physical switching and hardware configuration would provide more opportunities.