Will 2G and 3G sunsets leave roamers in the dark?

Telecoms.com periodically invites third parties to share their views on the industry’s most pressing issues. In this piece Mikael Schachne, VP Telco Market at BICS, ponders the implications of shutting down older mobile technologies for roaming customers.

As we continue to march towards next-generation networks, more and more countries are leaving 2G and 3G behind. While this needs to happen for telecoms to keep moving forwards (“out with the old and in with the new”), without the right contingencies in place, operators could be leaving lots of international roamers behind too. As networks around the world retire 2G or 3G at different rates, roaming interoperability is at risk, potentially widening the digital divide and affecting critical communications like access to emergency services.

Sunsets have of course been on the cards for a long time, with AT&T pulling the plug on 3G all the way back in 2017. Operators around the world are following suit at varying paces, but the number of completed sunsets is finally starting to pile up. For example, 2G has been completely retired in more than ten countries around the world, and in Europe, eight operators are planning to do the same before 2025, alongside 19 planned 3G sunsets in the same timeframe.

While these sunsets present short-term pain to operators (Verizon’s 3G shutdown cost it over a million subscriptions), the long-term gain is freeing up crucial spectrum and bandwidth for faster rollout of 4G and 5G networks. When O2 Telefónica sunsetted its 3G network in 2021 to drive more efficient 4G or 5G services, it claimed a 90% reduction in power consumption per transmitted byte.

The Risks for 2G/3G Roamers

Not only are networks being sunsetted on varying timelines, but certain operators, like in many countries across Africa, still rely heavily on 2G and 3G. This means roamers travelling from these networks to sunsetted countries (or vice-versa) will be unable to connect. This is problematic for several reasons:

Widening the digital divide: As 2G and 3G networks are phased out, those reliant on these legacy technologies may face limited or no connectivity options when travelling abroad. This would further widen the existing digital divide, disproportionately impacting users in regions with limited access to next-gen networks.

Safety Concerns: The discontinuation of 2G and 3G networks could hinder the ability of roamers to contact emergency services, potentially jeopardising public safety. Networks that have sunsetted 2G/3G carry voice traffic in a different way to older networks, via Voice over LTE (VoLTE), these two different methods are not inherently compatible, so roamers could find themselves unable to make voice calls, and therefore unable to contact emergency services.

Lost revenue for operators: Finally, the shift away from 2G and 3G networks poses challenges for operators as they risk losing revenue from roamers who can no longer access these networks. Operators need to carefully balance monetising new connectivity opportunities while ensuring the seamless experience of roamers transitioning from older networks.

To ensure customers are covered as much as possible when roaming in the sunset era, operators need to pursue roaming solutions that can allow their users to access otherwise inoperable networks.

VoLTE to the rescue?

VoLTE (Voice over LTE)-based solutions may be the answer to bridging the gap between 2G/3G and sunsetted networks. VoLTE enables voice calls to be transmitted over 4G networks, ensuring compatibility between these newer and older technologies.

While a 2G/3G network will not directly support VoLTE, solutions now exist to enable this data handover, essentially converting traditional circuit-switched voice calls to VoLTE so that a roaming connection can be established between the two networks. This bridges the interoperability gap and can allow operators to provide a seamless roaming experience for users transitioning from legacy networks to 4G/5G networks. VoLTE roaming also offers several benefits compared to older circuit-switched voice services, including improved voice quality, faster call setup times, and the ability to use data services simultaneously during voice calls – so roamers will benefit from this at the same time.

However, there are several challenges operators need to overcome to ensure these solutions are fit for purpose:

Network interoperability between operators: This can require extensive coordination and negotiation to reach the desired level of integration and suitable roaming agreements.

Pricing: Even with interoperability agreements in place, pricing for VoLTE services can vary among operators so roamers may be faced with differing pricing models or higher costs.

Device compatibility:  Older devices, particularly those native to a 2G/3G network, may not always be compatible with VoLTE. Naturally, this can limit the ability of roamers to benefit from the solution and create gaps in service availability.

(Sun)Setting the right balance

While the sunsetting of 2G and 3G networks is essential for the telco industry’s progress, a balance must be struck between embracing new technologies and safeguarding interoperability for roamers coming from legacy networks.

This will require collaboration on initiatives and setting up frameworks to ensure smooth (and safe) transitions for roamers. These standardisation efforts, like VoLTE roaming agreements, must be encouraged to enable seamless voice services across different networks. Operators also have a duty of care to support roaming customers in this transitional landscape. In practice, this might mean clear communication about network changes, guidance on device compatibility, and incentives for upgrading to 4G and 5G devices. This proactive approach could help mitigate potential disruptions and minimise the digital divide.

Finally, ensuring uninterrupted access to emergency services is crucial. While VoLTE solutions will go a long way here, operators may need to go beyond this with alternative emergency communication solutions, such as Emergency Services over IP (ESoIP), to guarantee roamers’ safety regardless of their device.

Progress in the telecoms industry is often described in the context of a “race”, whether it’s to 5G standalone, network slicing, or 6G – whatever the next target (and revenue driver) in sight is. That’s not necessarily a bad thing. Competition drives innovation, but it’s crucial that as an industry we work together to ensure we’re not leaving gaps or blind spots behind us. Not only do we have an obligation as an industry to ensure we are closing (not widening) the digital divide and ensuring equal access to emergency services, but without a solution in place, operators are leaving money on the table.

Mikaël joined the international division of Belgacom in 2001 which was then spun-off and merged with Swisscom International and MTN International. After having successfully led the product development and management of new international mobile data services such as Signalling, GPRS Roaming eXchange (GRX), SMS Hubbing, MMS Hubbing, Instant Roaming and Open Connectivity Roaming Hubbing, he’s now in charge of the Mobility and IoT Business at BICS. The portfolio is now supporting international mobile communications needs for more than 500 Mobile Operators and MVNOs across the world. He graduated from the Brussels University Applied Science Faculty (Belgium) as a Civil Electrical Engineer specialized in Electronic and Telecommunications and holds a master in Business-to-Business Marketing from the Vlerick Management School in Leuven, Belgium.

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