Bridging 4G and 5G: The Case for Cloud Native Diameter Routing Agents
As we head into the second half of 2025, the telecom industry is at a crossroads. While 5G has been heralded as the future, its adoption by communications service providers (CSPs) hasn’t been as rapid or widespread as many anticipated. The reality is that most providers still rely heavily on 4G networks, and the reasons are rooted in practical, not just strategic, challenges: new radio hardware requirements, spectrum limitations, unclear immediate return on investment, security concerns, and the daunting task of integrating new systems with legacy infrastructure.
The dual-core dilemma
Even after rolling out 5G New Radio, most CSPs continue to use 4G core infrastructure—specifically, non-standalone deployments—because it requires a lower initial investment and facilitates a faster rollout. This hybrid approach is likely to persist for years, especially in markets where the economic incentives to adopt full 5G standalone infrastructure aren’t yet compelling. As a result, CSPs face the operational burden of maintaining both 4G and 5G core networks, each with different technology stacks, vendors, and management models.
Enter cloud native: The path to modernization
The convergence of 5G and cloud native technologies offers CSPs a unique opportunity to rethink how they deploy, operate, and maintain their core networks. Cloud native principles—automation, orchestration, continuous integration and continuous delivery, and resource efficiency—are now essential for managing the complexity and scale of next-generation networks.
Deploying a 5G core means embracing a more heterogeneous and open ecosystem, often involving new or upgraded data centers and a mix of public and private cloud environments. In this context, the operational overhead of running both legacy private network function/virtual network function platforms and modern cloud native network function platforms can become unsustainable. Migrating critical core elements such as the Diameter Routing Agent (DRA) to a cloud native implementation is a strategic move that can unify infrastructure, reduce hardware and software sprawl, and streamline operations.
What makes a true cloud native DRA?
To fully realize these benefits, a cloud native DRA must be purpose-built—not just a containerized version of an old monolith. It should embody the following cloud native principles:
- Microservices architecture
- API-first design
- Statelessness
- Scalability and resilience
- Automation and observability
- Flexibility, portability, and manageability
However, implementing a DRA as a cloud native function isn’t a trivial task. Features such as Stream Control Transmission Protocol multihoming require creative engineering to work seamlessly in Kubernetes environments. Furthermore, a cloud native DRA must offer flexible routing policies to support both 4G and 5G services, as well as advanced signaling firewall capabilities to handle the complexities of serving subscribers both at home and when roaming.
Unlocking new insights and security
One of the most compelling advantages of a cloud native DRA is the ability to leverage mature Cloud Native Computing Foundation technologies for automation, lifecycle management, and observability. Tools such as Prometheus enable deep visibility into service behavior, so metrics such as service latency, network latency, and signaling errors can now be monitored in real time, replacing the need for expensive probes and limited ad hoc traces. This comprehensive telemetry facilitates actionable insights, allowing CSPs to optimize resource usage and quickly pinpoint issues in the core network.
Security is another critical area. With increasing mandates for encrypted signaling (Transport Layer Security/Datagram Transport Layer Security), traditional packet-based monitoring becomes less effective. A cloud native DRA can act as a secure, policy-driven feed for selected signaling messages, supporting troubleshooting, service assurance, and billing in ways that legacy probes cannot.
Discover Oracle Communications Cloud Native Core Diameter Routing Agent
Today’s CSPs face multiple challenges in their day-to-day operations and must continue to adapt to the changes in their network traffic. Hundreds and thousands of subscribers are moving around, changing their monthly or yearly options, and most importantly a huge amount of traffic data is flowing in. It’s time CSPs switch from being reactive to being proactive, especially given the opportunities their network data can offer.
To do this, CSPs need to evolve from being bare metal–centric and adopt cloud native methods of managing their networks. This will help them pave the way for a successful cloud network transformation. Our solution has been built from scratch based on Cloud Native Computing Foundation principles, and it offers a containerized DRA function that can be integrated with any cloud native environment. We offer our Cloud Native Core DRA solution as a convergent function with our 5G signaling network function (NF) over a common cloud native environment, which helps CSPs optimize their network operations and monetize their investments. Our cloud native network functions not only offer microservices-based options for CSPs but also provide full-scale methods to enable optimizations in 5G networks, and they facilitate better forecasting for NF routing and dimensioning.
Our Cloud Native Core DRA solution comes with feature-rich capabilities, including centralized routing, traffic management, load balancing, and integrated 4G applications, creating an architecture that enables IMS and LTE networks to be truly elastic and adapt to increasing service and traffic demands while optimizing network resources. It is purpose-built for 4G use cases, rapid deployment, and quick business value, and it offers a multitude of options—such as value-based user subscriptions, traffic visibility, and network optimization for better customer experiences—across both enterprise applications and the core network.
Cloud native DRA: A strategic imperative
For CSPs navigating the transition between 4G and 5G, adopting a cloud native DRA is more than a technical upgrade—it’s a strategic imperative. It streamlines operations, enhances agility, and provides the visibility and security needed for tomorrow’s networks. In a world where hybrid cores will be the norm for years to come, a true cloud native DRA is the key to unlocking operational efficiency and future-ready innovation.