IoT fears as AT&T prepares to turn off 3G

  • February 16, 2022
  • Steve Rogerson

AT&T is phasing out its 3G network this month in a move that could leave many IoT users without connectivity. Companies have issued warnings that some IoT devices will no longer work when the network closes.

T-Mobile says it will follow suit by closing its 3G network in the USA in July and Verizon plans to do the same at the end of the year.

AT&T is encouraging businesses to adopt 4G LTE or LTE-M service and migrate from existing 2G and 3G devices as soon as possible. This can help avoid uncertainty, maintain business continuity, gain improved service and save costs. Mobile carriers plan to end service on their 2G and 3G networks, freeing up spectrum to redeploy and better accommodate newer technologies and services.

With the introduction of LTE-M and NB-IoT, in addition to 4G LTE, businesses have the option to have their endpoints connected to a network that better meets their requirements.

AT&T estimates that more than half of the more than 125 million cellular IoT devices deployed run on 2G and 3G networks and many of the over 13.5 million fleet vehicles on the road are more than seven years old.

Market watcher Juniper Research says the closure of 2G and 3G networks will drive low-power wide-area (LPWA) cellular deployments. It predicts the cellular IoT market to reach $61bn by 2026, up from $31bn this year.

Juniper’s report urged operators to migrate IoT connections on legacy networks to networks that support LPWA technologies. It anticipated that demand from enterprises for low-cost monitoring technologies, enabled by LPWA networks, will increase as legacy networks are shut off over the next four years.

“Operators must educate users on the suitability of LPWA as a replacement technology for legacy networks,” said research co-author Charles Bowman. “However, many IoT networks cannot solely rely on LPWA technologies. More comprehensive technologies, such as 5G, must underpin IoT network architectures and work in tandem with LPWA technologies to maximise the value of IoT services.”

NimbeLink has said some of its Skywire embedded modems will fail to connect to the AT&T network after February 22. Specifically, these are the NL-SW-LTE-TNAG, NL-SW-LTE-TNAG-B, NL-SW-LTE-TC4NAG, NL-SW-LTE-S7588-T and NL-SW-LTE-S7588-T-C. Additionally, the NL-SW-LTE-S7588-V and NL-SW-LTE-S7588-V-B will be affected if the user loaded AT&T firmware onto the Verizon SKU from NimbeLink.

AT&T says the move is to make room for an even better network.

“To bring you faster speeds and new features, we’re excited to upgrade America’s best network,” said a company statement. “One change we’re making is shutting down our 3G network in February 2022.”

It said it was important to check model numbers of devices to make sure they are supported after the 3G network shuts down. Those not on the list will no longer work after next week’s shutdown.

For example, AT&T says it will no longer activate phones that don’t support HD Voice since they won’t be compatible to work on the network when 3G shuts down.

Those switching SIM cards between devices should make sure the device they’re moving the SIM card to will work on the network.

Those using AT&T MicroCell may get a free replacement device compatible with AT&T’s LTE network.

Talk and data services will only work for AT&T wireless and prepaid phones and devices that support at least 4G LTE and HD Voice.

After shutting down the 3G network, data-only devices will only work if they support 4G LTE speeds and higher.