Drei Austria and Cellusys Deliver World’s First Steering of Roaming for 5G Standalone
Drei Austria, a leading mobile operator, and Cellusys, the #1 provider of roaming and mobile security solutions, have achieved a world first: successfully demonstrating Steering of Roaming for 5G Standalone (SA) networks.
This milestone proves that both companies are at the forefront of roaming innovation, going beyond current standards and vendor readiness to make 5G SA roaming work end-to-end.
Why This Is Important
When customers travel abroad, their phones connect to a partner network. Steering of Roaming is the technology that ensures subscribers are guided to the best possible network for quality, reliability, and cost.
In earlier generations of mobile networks, this was relatively straightforward. But 5G Standalone introduces a new environment, and the associated standards to enable this have not been fully implemented by all network suppliers. This has made it difficult for operators worldwide to deliver a consistent 5G roaming experience.
Drei Austria and Cellusys have overcome these barriers and shown that it can be done today. By combining Drei’s operational expertise with Cellusys’ innovation in roaming solutions, the two companies have implemented a working system that ensures subscribers can enjoy a reliable and smooth 5G roaming experience.
A Step Ahead of Standards
The official industry standard that defines Steering of Roaming for 5G SA has left some gaps, and several core network components are not yet ready for full deployment. Instead of waiting, Drei Austria and Cellusys collaborated to find practical solutions, bridging these gaps and proving that seamless roaming is possible now.
This approach demonstrates leadership not only in technology but also in commitment to delivering real value to customers. Drei Austria and Cellusys have thus not only demonstrated technical feasibility but also shown that real-world deployment requires going above and beyond: validating vendor claims, building interim workarounds, and pushing for full support of the standard across all core elements
“We believe that 5G SA roaming is the future. But having a spec is not enough—what matters is whether all the pieces are in place. With Cellusys, we’ve proven that end-to-end 5G SA Steering of Roaming works – even when many existing network elements aren’t fully ready.”
– Bernhard Sommer, Head of Wholesale – Strategy and Services, Drei Austria
“Standards like 29.550 set the direction. But real networks, real roaming, expose the cracks. Our work with Drei shows that being a leader means not waiting for perfection – you build, you test, you validate, you compensate. And you deliver.”
– Daniel McTague, CTO, Cellusys
About Drei Austria
Hutchison Drei Austria GmbH is a 100% subsidiary of CK Hutchison Holdings Limited (Hong Kong) and a member of the 3Group Europe. As a leading telecommunications provider in Austria, the company offers mobile telephony, internet, fixed-line services, television, and business solutions from a single source.
About Cellusys
Founded in 2005, Cellusys is the industry leader in roaming, fraud & security and analytics solutions for communication service providers. The company offers a wide range of products and services designed to give mobile operators visibility and control of their signalling and data traffic. Cellusys has won numerous innovation awards and is ranked as #1 vendor in roaming and security, by both ROCCO and Kaleido, excelling on Net Promoter Score.
To learn more, visit www.cellusys.com.
Read more about Cellusys roaming solutions.