Deutsche Telekom’s 5G Core Shift: Why the Move from Ericsson to Mavenir Matters
Deutsche Telekom‘s transition from Ericsson to Mavenir as its primary 5G standalone core provider is more than a vendor swap—it represents a fundamental rethinking of how Tier 1 operators architect, operate, and monetize their networks in the cloud-native era.
Why Deutsche Telekom Moved Its 5G Standalone Core Away from Ericsson
Deutsche Telekom’s core network vendor history reads like a geopolitical and technological timeline. When European regulators effectively shut Huawei out of critical infrastructure, Deutsche Telekom turned to Ericsson for its virtual evolved packet core (vEPC), anchoring both 4G and non-standalone 5G traffic. That decision made strategic sense at the time. But as the operator’s cloud ambitions matured, a new set of priorities emerged—ones that Ericsson’s full-stack model was structurally ill-suited to serve.
Today, Mavenir carries all standalone 5G traffic in Germany. Ericsson remains active on the legacy 4G and non-standalone 5G side, but with Deutsche Telekom planning to phase out its 2G network by June 2028 and retire its non-standalone core around the same period, the trajectory is clear. Mavenir’s converged 4G/5G packet core is positioned to absorb the entire mobile traffic load as legacy infrastructure is decommissioned.
How Deutsche Telekom’s Horizontal TelCo Cloud Is Reshaping Vendor Selection
The engine driving this vendor transition is Deutsche Telekom’s Horizontal TelCo Cloud (HTC)—an internal architecture initiative that replaces dozens of siloed, vendor-wrapped network functions with a single, standardized, Kubernetes-based cloud platform.
Kubernetes-Based Infrastructure and the End of Vendor-Bundled Network Stacks
Under the old model, Deutsche Telekom operated more than 50 core network applications, each bundled with its own cloud infrastructure stack. The inefficiency was structural: separate compute environments, separate orchestration layers, and separate operational toolchains for every function. HTC collapses this complexity by introducing a shared infrastructure layer—T-CaaS, the operator’s containers-as-a-service platform—on top of which all core network functions run as lightweight, cloud-native applications.
This architectural shift fundamentally changes what Deutsche Telekom demands from its vendors. Rather than buying a full-stack solution, the operator wants application-layer software that integrates cleanly into its own platform. Mavenir, with its cloud-native, containerized packet core, fits that model. Ericsson, which continues to develop and sell its own cloud infrastructure platforms—CNIS and NFVI—does not, at least not yet. Nokia made this pivot in 2023 by divesting its container services and infrastructure software to Red Hat. Ericsson has not followed suit, and that divergence is now showing up in operator decisions.
How Deutsche Telekom and Sylva Are Building a Common Telco Cloud Standard
Deutsche Telekom is not building HTC as a proprietary moat. The operator is actively contributing components to Sylva, the Linux Foundation‘s initiative to create a common telco cloud framework. Elements of T-CaaS, including a host-based routing system, are being fed into Sylva, and there is internal belief that the two frameworks could eventually fully converge. Orange‘s Telco Cloud follows a parallel path, and its CTO has publicly welcomed Deutsche Telekom’s growing engagement with the Sylva project. This convergence around open-source standards is significant: it suggests that HTC-style architectures could become the industry baseline, not a single operator’s experiment.
Measurable Results: Network Slicing, Energy Savings, and 5G Application Performance
The strategic architecture story is compelling on its own, but what makes Deutsche Telekom’s Mavenir deployment particularly noteworthy is the operational and commercial results it is already producing.
From Enterprise Niche to Mainstream: 5G Network Slicing for Consumer Applications
Deutsche Telekom has now launched three commercial 5G network slicing use cases in Germany—mobile journalism, gaming, and most recently, video telephony. The video telephony deployment, built on Mavenir’s 5G Standalone core, integrates L4S (Low Latency, Low Loss, Scalable Throughput) technology to deliver guaranteed, application-aware performance. Apple‘s FaceTime, with the upcoming iOS 26 release, is the first application to leverage these capabilities at consumer scale. This marks a meaningful inflection point: network slicing is no longer a proof-of-concept reserved for enterprise verticals. It is being delivered to mainstream consumers, redefining expectations for mobile video quality.
How Deutsche Telekom and Mavenir Achieved 65% Energy Savings in Live 5G Core Testing
In parallel, Deutsche Telekom and Mavenir have validated up to 65% energy savings in live 5G core network testing through a Full Stack Energy Efficiency approach. This combines dynamic software and hardware scaling with AI-driven resource management to pursue what Deutsche Telekom describes as a “zero bit and zero watt” core—consuming no energy when carrying no traffic. Mavenir’s cloud-native software features, several deployed commercially for the first time, are central to this achievement. As energy costs and sustainability commitments become boardroom-level concerns for operators globally, this kind of measurable efficiency gain carries significant weight—both financially and reputationally.
Strategic Implications for Tier 1 Operators and 5G Core Vendors
Deutsche Telekom’s trajectory offers a strategic blueprint that other Tier 1 operators are likely to study closely, and several implications stand out for network strategists and technology decision-makers.
First, the era of vendor-bundled cloud infrastructure in the core is ending for large operators. Telcos with the scale and engineering capability to build horizontal platforms will increasingly demand application-only software from their vendors. Vendors that cannot or will not decouple their applications from their infrastructure stacks face a shrinking addressable market at the top of the operator tier.
Second, network slicing is crossing from enterprise niche to consumer mainstream. The combination of 5G Standalone architecture, L4S, and intelligent orchestration is enabling operators to offer differentiated, guaranteed-quality experiences for specific applications. This creates new monetization pathways that move beyond flat-rate data plans.
Third, energy efficiency is becoming a first-order network design criterion, not an afterthought. Operators facing rising power costs and net-zero commitments will increasingly evaluate core network software on its energy profile alongside performance and cost metrics.
For vendors, the message is equally direct: cloud-native agility, open-platform compatibility, and AI-driven automation are no longer differentiators—they are table stakes for competing at the Tier 1 level. Deutsche Telekom’s cloud jump is a signal worth watching carefully.
