Maturity of 5G mobile packet core as a cloud workload

Today, Comcast announced that it will be running its 5G mobile packet core, developed by Nokia, entirely on the AWS public cloud. With this deployment, we have now reached a point in the evolution of the public cloud with capabilities to support network functions, where the 5G mobile core is now a mature and proven workload, that can run on AWS in a variety of deployment scenarios, without the need for experimentation, extended engineering engagement, or deep partner involvement.

Evolving the AWS cloud for telco network workloads

Since the launch of Amazon S3 and Amazon EC2 in 2006, AWS has continued to innovate and evolve to support new categories of workloads, deployment scenarios, and evolving regulatory requirements. Telco line of business workloads, particularly those involved in building network infrastructure— containerized network functions (CNFs) —were a new category for the cloud when we began evaluating them in 2018. The journey started with 1) understanding new cloud deployment models needed (outside of the AWS Regions), then 2) building strong relationships and working with ISVs to understand and refactor network function software, then 3) enhancing AWS services like Amazon EC2, Amazon VPC, Amazon NLB, Amazon EKS, and others to support these network functions, and 4) finally, learning through trials and live network deployments to shape operational aspects, and refine AWS services further. As part of 1) we built a continuum of AWS infrastructure services that spans from AWS Regions to customers’ edge locations with services, such as AWS Local Zones and AWS Outposts, to create flexibility and choice for hosting network functions at appropriate locations. For 2) and 3), we worked with ISVs to understand software implementations of telco protocols and 3GPP standards, to inform enhancements to our services. We also recommended software modifications to make the software more cloud native. Cloud native in this context implies implementations that can take full advantage of the benefits of the cloud such as horizontal scaling (elasticity), operational efficiency, agility and rapid innovation, while adopting cloud resiliency and security architectures. Finally, exercise in 4) helped us apply cloud operational principles and tools to networks. More details on this cloud evolution are described in this whitepaper.

From experiments to production networks

The first milestone in this journey was a proof-of-concept of an LTE packet core gateway on an early prototype of AWS Outposts in an operator’s lab in December 2018. From then on, we successively went through on-boarding, proofs-of concept, and trials with 5G mobile core components from different vendor and in different deployment scenarios.

The first cloud native 5G core network. The first exercise of building a production network with 5G core on the cloud began with Dish Wireless in 2021. Dish Wireless had a vision of building a 5G network with modern software CI/CD (continuous integration/delivery) flows for software, very low operational cost, and the ability to dynamically create and offer new sets of services on top. This visionary initiative provided an opportunity to build a greenfield cloud native production network from the grounds up. We took advantage of the flexibility in placing 5G mobile core network functions in AWS Regions and AWS Local Zones, spread across the US to cover different markets. We relied on AWS Direct Connect for portions of the backhaul, as Dish Wireless did not have existing data centers or an established fiber network in the ground. The details of the deployment architecture is described in this blog. The Dish Wireless network reached 70% national coverage in June 2023.

Breaking through the constraints of brownfield operators. In May 2024, O2 Telefónica announced its 5G Cloud Core – a new 5G cloud network built entirely in the cloud, using technologies from European network equipment provider Nokia and AWS. It was the first time a telecom operator has migrated its existing network and customers to a new 5G cloud network running on AWS. O2 Telefónica had existing assets of data centers, backhaul and established internet peering points. We had to map out a deployment scenario that used an AWS Region, while reusing some of the existing architecture for other network components, their existing transport network, and internet peering points. And now, with Comcast 5G Cloud Core, we validated the effectiveness of the architecture within weeks and enabled implementation within months, demonstrating agility and adaptability of getting to live networks very rapidly. Building on the experience of the Dish Wireless network, and progress in cloud nativeness of the network function software, we did not require deep engagement of AWS engineering teams or ISV teams. Having a common set of APIs that ensured operational consistency across the cloud edge continuum, coupled with cloud-native automation capabilities and lifecycle management, has set the foundation for future enhancements for Telefónica and Comcast to scale their network across the AWS edge continuum and migrate other components of their 5G networks.

Addressing Digital Sovereignty and other regulations. Telcos are part of a regulated industry. They require control and assurance that cloud providers will not access or use customer data for any purpose without their agreement, as well as access to the strongest sovereignty controls for running 5G core on the cloud. As part of increased transparency, we had NCC Group, a leading cybersecurity consulting firm based in the United Kingdom, independently attest to the high bar of security that AWS provides for 5G mobile core workloads. We developed AWS Key Management Service (AWS KMS) External Key Store (XKS), that supports the regulatory need of storing and using encryption keys outside the AWS. In 2023, we also announced that we will launch the AWS European Sovereign Cloud, a new, independent cloud for Europe, to meet the most stringent regulatory data residency and operational requirements. Only EU-resident AWS employees who are located in the EU will have control of the operations and support for the AWS European Sovereign Cloud. For customers with enhanced data residency needs, the AWS European Sovereign Cloud will allow customers to keep all metadata they create in the EU, and will feature its own billing and usage metering systems.

Tapping deeper into the value of the cloud and AWS differentiation

The initial expectation of telcos from us was to be able to run 5G core workloads on the cloud in live production networks at the scale, reliability, performance, security expected for telco networks. It was expected to be at lower TCO and increased operational simplicity and agility. We are now expanding beyond that to tap deeper into the value of the cloud and address use cases not possible with traditional on-premises private infrastructure models. Additionally, beyond the general cloud value proposition, we are also bringing in AWS specific technology differentiators to change traditional approaches and ecosystems.

Expansion of cloud use cases. In 2023, we also started seeing an expansion of use cases. a/ Multi-tenanted, API driven, 5G core SaaS deployments. The cloud is multi-tenanted and a very agile development environment. Developers share infrastructure and through APIs, create and deploy new applications, easily and quickly. Similar to these applications, the 5G core network function can be offered as a multi-tenant mobile core, to be used by multiple MVNOs, MNOs and private network deployments. Working Group Two (WG2), which is now a part of Cisco Systems, has developed a fully cloud native mobile packet core that they now offer in SaaS model on AWS. With a few API calls, an MVNO can integrate and deploy a 5G mobile packet core instance to build their network and start offering a host of connectivity services. In 2023, Mobi, a wireless carrier, announced a nationwide cloud native MVNO service on T-Mobile’s network using WG2’s 5G mobile core, hosted on AWS. Three Group Solutions transformed its MVNE platform with a fully cloud-native, complete mobile solution, with help from AWS Partners CSG and WG2. b/ Disaster recovery and high availability 5G core. Another property of the cloud is elasticity – you can scale infrastructure resources up or down, based on need, paying for only what you use. This lends itself to very cost efficient high availability (HA) and disaster recovery (DR) architectures for network workloads. One cloud model is an active-active scenario where a small percentage of mobile core traffic runs on network functions in AWS Regions and bulk of it runs on on-prem instantiations of the core. In the case of a failure, on-prem traffic shifts to the AWS Regions, increasing infrastructure resources, dynamically, as needed. In another scenario, HA is implemented with redundant copies on-prem and in AWS Regions or across AWS Availability Zones in an AWS Region. Details of these architectures are in this blog.

Bringing in AWS differentiation. In addition to just moving to the cloud and using cloud properties, we are also leveraging some of the key AWS innovations to differentiate further. AWS develops custom chips in-house, focused on opportunities to innovate for the cloud at the silicon level. In 2018, we launched the Graviton chip and instances, based on ARM architecture and we are now on the 4th generation of these chips. Telco network workloads, especially the physical layers of the RAN stack are performance demanding and Graviton gives the best price/performance compared to compute instances on x86 and other architecture. Secondly RAN portion of the network consumes in the ballpark of 70% of power in telco networks. ARM is an extremely power efficient architecture, resulting in significant power savings in running the network. Lastly, the industry for a long time has been dependent on one architecture, and this gives a choice to the ISVs and customers of an alternate silicon ecosystem. NTT DOCOMO saw a 70% reduction in power consumption on an average using Graviton based instances. Nokia is seeing significant performance gains in their RAN stack on Graviton based AWS instances, and compatible with the physical layer which runs on ARM based Smart NICs.

Conclusion

Since its inception in 2006, AWS has been evolving the cloud to address new categories of workloads, driven by different industry verticals as well as to meet emerging regulatory requirements from different parts of the world. We have been on a journey of making the cloud capable of running network functions in general, and specifically 5G mobile core networks at the scale, performance, resiliency, security demanded by telco networks, while reducing the total cost of ownership and bringing in automated operations and agility. We have done this by factoring in considerations of regulators around security, data privacy and sovereignty. We have deployed production 5G mobile cores with tier-1 operators like Dish Wireless and now, Comcast in the US, Telefonica in Europe and also MVNOs like Mobi, covering a range of deployment scenarios and backhaul, internet peering, and telco edge data center architectures. Through instantiations of DR/HA architectures and performance/power measurements on Graviton, we have demonstrated the value of the cloud and AWS beyond what traditional deployments can do. With the Comcast 5G core, we are entering a phase where these workloads are not specialized workloads anymore, but just like any other mature workload that can be seamlessly run in the AWS Regions or AWS edge.