Navigating the path to 5G SA roaming

3 min read Networks & Network Services
By Eyal Zach, director product management, network roaming, TOMIA

Worldwide, the number of 5G connections is projected to grow to 1.1 billion by 2025. Faster data speeds, increased reliability, ultra-low latency, new use cases leveraging 5G slicing and QoS capabilities and more are the sought-after connectivity ‘gold’ that businesses and consumers are looking for from their network providers.

5G networks will also supercharge the IoT opportunity and pave the way for the ‘IoT World’ to become a reality, with connected cars, public transport, buildings, homes and digital devices.

IoT will certainly accelerate 5G roll-out. Eye-catching consumer applications like AR gaming give consumers a taste of the quality, speed and experience that 5G connectivity can provide.

With the onset of Covid-19, consumer roaming traffic declined considerably. TOMIA’s own data detected an average drop in consumer roaming traffic of 70 per cent in 2020. The good news for operators is that the same data revealed the IoT device traffic that had been undetected until then. During the pandemic, IoT devices accounted for 40 per cent of roaming traffic in March when lockdown started, rising to 70 per cent in May.

Now, mobile network operators, IP exchanges and value-added services (VAS) providers are actively exploring ways to recover consumer roaming revenues and implement a successful charging model for IoT roaming even if some are not quite ready to implement it yet.

Consumer roaming traffic is expected to return to pre-Covid levels by the end of 2023. However, a real opportunity for telecom providers is to transition to 5G-ready infrastructure that enables them to optimise the potential revenue streams from IoT roaming, offer differentiated services to the enterprise market and move up the value chain.

A tale of two paths

Of course, operators face plenty of technical challenges and the temptation to wait for universally agreed standards is considerable, as well as deciding which path towards 5G to take.

There are two approaches currently available: Non-Standalone Architecture (NSA) and Standalone Architecture (SA). NSA is the natural or easier evolution to 5G. The decision will be when to invest in the full-blown SA architecture, and with whom to enable 5G roaming.

The main difference between them is that NSA anchors in the 4G core, while SA introduces a completely new 5G core network. The majority of 5G roaming is currently delivered over NSA networks, to enable higher bandwidth and better user experience.

However, this approach can’t support all 5G use cases. It’s fine for video streaming and online gaming, but ultra-reliable and low latency communications use cases, like connected cars and telesurgery, require real-time connectivity, flawless reliability levels and dedicated slicing to ensure the quality of service.

A pole-VoLTE into 5G

Although piggybacking on 4G or 5G NSA is presented as a valid option, the ultimate goal is to fully exploit 5G’s potential in the Standalone (SA) network. The industry can expect to see more 5G roaming agreements, once more SA networks are in place, but currently, there’s still a lack of clarity around 5G roaming models, especially for enterprises and IoT.

However, before we set our sights on the roll-out of 5G on SA networks, we need to clear the decks with the sunsetting of 2G/3G. The journey from 2G/3G to 5G calls for network operators to support full network automation and virtualisation.

The first step is to move all voice transactions over from Circuit Switch to Packet Switch base, also known as Voice over Long Term Evolution (VoLTE).

VoLTE enables improved and innovative voice and communication services across smartphones and other devices, and, in fact, the only fall back option for 5G voice (Vo5G).

In other words, VoLTE roaming must act as a predecessor of 5G roaming – all network value added services must support VoLTE to ensure the proper customer experience for consumers and businesses when it comes to 5G use.

A slice of the 5G cake

Network slices, one of the main promises of 5G SA networks, will increase in complexity when it comes to the management of roaming agreements, implementation of new business models, and the market is already witnessing a consolidation of roaming players and the appearance of aggregators to help other smaller operators to deal with the complexity of 5G roaming.

However, charging per 5G network slice - only possible with SA - will be also driven by specific IoT use cases such as those that are business-critical, or things like autonomous driving and telemedicine, rather than retail consumers.

But it won’t happen overnight. There'll be a gradual transition of IoT to 5G, but for now, the majority of cellular connectivity is still via existing infrastructure, with most devices connected via WiFi.

It means roaming vendors should ensure their suite of value-added services support legacy technologies, including 2G, 3G, 4G and VoLTE, as not all roaming traffic will immediately transition to 5G networks, so says Juniper Research.

Analytics - connecting IoT and revenue 

This will entail a higher level of complexity, as operators will be handling traffic over at least three different technologies at the same time, and there will be a requirement for interoperability and interworking.

Additionally, standard charging per financial month or year will not be suitable for IoT as it does not truly reflect the value of the data. The data-charging journey is one of transition from usage-based charging to the number of devices - already happening - to finally becoming per service, or based on content type.

Analytics will therefore play a more fundamental role in measuring and ensuring properly agreed SLA and KPIs and detecting permanent roaming behaviour – a possible opportunity to monetise devices that only use signalling. With analytical insights, network operators will be able to improve services and ensure incremental revenue.

The rewards for 5G SA first movers outweigh the challenges and that new technology capable of managing the complete end-to-end 5G lifecycle opens up a promising route forward.