Spark says its LoRaWan network will be operating in four centres by Christmas. The network goes live first in Auckland, Wellington, Christchurch and Hamilton.

The company says 16 more cities will be added to the network early in next year. By mid-2018 it will reach 70 percent of the population.

Spark is playing catch-up in IoT network technology. Two networks, Thinxtra and locally owned Kotahinet, already have wide coverage reaching most of mainland New Zealand.

It's a crowded market. Chorus has recently trialled its own LoRaWan IoT network while Vodafone expects to launch its network next year.

For its trial network, Chorus worked with Vianet, which is owned by the same parent company as Visionstream. Chorus has a natural advantage when it comes to building a network as it owns telephone poles, cabinets, exchanges and masts throughout the country. The company is also using redundant copper telephone network to deliver power to IoT access points.

The new Spark IoT network is being built by Kordia, which also put the Sigfox network in place. Spark uses two network technologies: LoRa and M1. The LoRa network is largely ready while Spark says the M1 network will start commercial operation in the first part of 2018. LoRa uses unlicensed spectrum while M1 piggybacks off the cellular network.

Spark says it will also invest in a third network, Narrowband-IoT, later when the technology is more mature.