Cellular technology, evolving from 2G, 3G, 4G/LTE and now 5G, is one of the main pillars of industrial IoT networks. It enables connectivity with thousands of remote devices deployed in the field, across industries and use cases.

Like any technology, cellular technology evolves over time as new releases of 3GPP specifications are developed, implemented by vendors, and adopted by services providers or private networks operators. Today, the main market trend is 4G/LTE services, while new 5G services are now appearing around the world.

What about legacy 2G and 3G services still in use on many industrial deployments around the world?

The number of cellular devices reached 8.6 billion in 2021 and associated applications are growing exponentially.  Repurposing spectrum previously utilized on 2G and 3G networks for use with faster and more efficient 4G/LTE and 5G services is part of all mobile network operators planning. The dates for the sunset of 2G and 3G technologies vary by world region and mobile operator. End users must be aware of these sunset dates and migrate to 4G/LTE connectivity prior to these dates to prevent loss of connectivity.

2G and 3G sunset overview

While the below list of sunset schedules for worldwide 2G and 3G mobile operators is not exhaustive, it supports you to start planning for the impact on your industrial IoT network.

• AT&T -3G services were sunset on February 22, 2022, while the 2G network was stopped in 2017.
• Bell Canada -3G CDMA network closed on April 30, 2019.
• Orange France -2G will sunset by end of 2025.
• Rogers Canada -2G and 3G 1900MHz network shut down on June 7^th, 2021, and 2G on 850MHz on December 31, 2021.
• Sprint -3G services sunset on March 31, 2022.
• Telefonica Germany -3G sunset on December 2021.
• Telstra Australia -3G services will sunset on June 2024.
• T-Mobile -3G services will sunset on July 1, 2022.
• Verizon -3G services will sunset on December 31, 2022.
• Vodafone UK -3G will sunset in 2023.

Industrial IoT routers -modularity a KEY requirement

Industrial IoT networks leveraging cellular technologies are generally deployed for 5-10 years. The mobile phones industry, with its nearly 15 billion devices [Statista], has a shorter life span of 18-30 months [Statista U.S.]. This represents a challenge for modem vendors. They must renew their chipset to align with new 3GPP releases, while maintaining older generations of modem chipsets and firmware. That is why the deployment of industrial IoT routers such as the latest Cisco IR series with modular cellular interface enables future proofing and smooth evolution of cellular technology without replacing all equipment.

Cisco industrial IoT routers -preparing for 3G sunset

All Cisco industrial IoT routers support 4G/LTE, even those purchased in the last 10 years. It means your industrial IoT network is mostly ready for the 3G sunset. The following best practices will ensure a smooth transition from 3G to 4G.

• Run one of the most recent Cisco IOS or Cisco IOS-XE releases
• Upgrade your modem firmware to the most recent release available on Cisco.com for your modem type. Be aware that Cisco IOS upgrades don't update your modem's firmware.
• Validate that your SIM subscription is 4G/LTE enabled and review your data plan as appropriate.
• Lock your cellular interface configuration to "all-LTE-only" to avoid any 3G fallback that may disrupt the communications.
• Monitor the 4G/LTE signal quality in case radio coverage is different between 3G and 4G/LTE services.
• Review Cisco's router antennas guide in case you would like to plan for new 4G/LTE (e.g. CBRS B48) or 5G (e.g. n77, n78) frequency bands. If required, plan to upgrade the antennas accordingly.
• Automation and network management tools and security best practices don't require changes.