How can Operators prepare for 3G Sunsets?
All three of the major mobile operators in the US have shuttered their 3G networks, but the lessons they learned can be applied to carriers around the world.
One of the biggest hurdles for retiring the networks is the impact on roaming between carriers. There needs to be a bridge between the mobile generations to support roaming interoperability to provide a better customer experience and monetization for operators.
Syniverse has built a first of its kind platform to address both the inbound and outbound roaming issues associated with the retirement of 2G and 3G networks.
The opportunities for sunsetting 2G and 3G networks are ripe. GSMA Intelligence’s Spectrum Navigator places the number of operators in Europe which have already completed 3G sunsets at 22, with 41 more scheduled by 2030.
By closing down their 3G networks, US mobile operators were able to sunset their RAN to free up spectrum while shift operating costs to their 5G network builds.
Decommissioning legacy circuit-switched networks also helps operators accommodate the increased 4G and 5G bandwidth demands of mobile and Internet of Things (IoT) devices that are ramping up across numerous verticals.
A US pathway to sunsets
Verizon shuttered its 3G CDMA network at year-end 2022, three years after initially announcing a closure. It started actively decommissioning its 3G network in 2016 but extended the shut off date from 2019 to the end of 2022 to give customers more time to prepare for and minimize disruptions to their services as they transitioned to newer and more advanced technologies.
AT&T announced that it phased out its 3G network in February 2022 while T-Mobile shut down its 3G UMTS network in July of the same year.
Roaming challenges loom large
According to a blog by Brian Beach, Product Owner – Senior Director, MNOs need the capability to support subscribers who either roam into a mobile network that no longer supports 3G or roam in from a network that has yet to implement VoLTE roaming.
He noted most the common consequence when an operator shuts down its legacy network is inability to support circuit-switched fallback, which allows roamers coming from home operators that do not support VoLTE, or VoLTE roaming, to visit its network.
Beach stated this issue causes a secondary problem. When a carrier shuts down a 3G network, it instantly limits its ability to support the operator’s own subscribers when they decide to roam into a visited network that doesn’t support VoLTE roaming.
There’s also a need facilitate voice and short message service (SMS) and the clearing, settlement, and near-trade as well for a full end-to-end solution.
To keep customers from being stranded on an island, many operators are compelled to maintain legacy equipment to support their outbound roaming subscribers.
Operators need to change their behavior to benefit from Syniverse’s solution.
The uptake for VoLTE has been very slow, or at least slower than expected across the industry. With 5G non-standalone, 3G circuit-switched fallback for voice is not an option so VoLTE roaming needs to be deployed in a roaming scenario. That has been one of the biggest obstacles that has kept 5G non-standalone from being more widely deployed today.
Syniverse tackles inbound roaming challenges
Syniverse collaborated with both Verizon and AT&T to help them overcome their roaming problems when they retired their 3G networks. The operators tapped into Syniverse’s Evolved Mobility to resolve those issues.
Both operators used Evolved Mobility to provision inbound roaming with VoLTE enabled devices from international mobile operators who hadn’t yet launched VoLTE on their networks.
Specifically, Evolved Mobility bridged the gap between 3G and VoLTE to provision roaming between operators who are at various stages of implementing and supporting VoLTE.
By essentially becoming the “home operator,” Syniverse can support the main operating components, including the IMS core and telephony application servers, but also the interworking services.
All of which sets-up a scenario where Evolved Mobility makes it seem as if the home operator has VoLTE in its own core, removing the need for circuit-switched fallback to establish voice and ultimately data services.
Beach noted that by implementing an effective 3G-to-VoLTE roaming product, both the visited and home network can maintain the method of roaming that’s best for them, which in turn meets the needs of both operators and end users.