AT&T has turned on its second low-power wide area network designed for IoT, with the operator’s narrowband Internet of Things (NB-IoT) network officially going live nationwide on Monday.

The new NB-IoT network complements AT&T’s existing LTE-M network, both of which are built to handle IoT connections on licensed spectrum, explained Chris Penrose, president of IoT Solutions at AT&T Business, in a blog post announcing the news.

“Having both networks offers our business customers more options to implement IoT solutions with security, interoperability, and lower costs,” Penrose wrote.

AT&T launched its LTE-M network for IoT in the U.S. in 2017, and first announced plans for a complementary NB-IoT network in June 2018. Today’s launch follows the completion of software upgrades at AT&T’s 4G LTE cell sites across the U.S.

 AT&T’s LTE-M network also has been up and running in Mexico since 2017, and AT&T plans to start deploying NB-IoT in the country later this year.

T-Mobile was the first carrier to launch an NB-IoT network in the U.S., which went live in July 2018.

Penrose said AT&T’s NB-IoT network is “a big step toward massive IoT and 5G,” and the technology is best suited for use cases like simple sensors, door locks, and industrial monitors that only require basic data requirements.

LTE-M provides greater bandwidth, capable of supporting mobility, voice-over services, and firmware and software updates with applications like pet trackers, medical wearables, and asset management, having already been deployed, according to Penrose.  

AT&T currently offers plans starting at $5 per year per device, and Penrose said his team is working with vendors to certify $5 modules that connect devices to the NB-IoT network.

“Multi-mode modules that support both NB-IoT and LTE-M are not far behind,” Penrose wrote.