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ONF Announces New Cloud-Native, Software Defined SD-Core Project Addressing 5G Mobile Core

Optimized for Private 5G and Industry 4.0 projects, SD-Core enables SaaS style delivery of Connectivity-as-a-Service

JUNE 24, 2021, MENLO PARK, Calif.  - Furthering the open source movement for carrier and private enterprise 5G networks, the Open Networking Foundation (ONF) today announced the launch of the SD-Core™ project building an open source 5G/4G disaggregated mobile core optimized for emerging private 5G and enterprise use cases.

Hybrid deployments mixing public and edge clouds is fast emerging as the dominant model for building hyperscaler, telco and enterprise networks. Network owners and application developers are demanding the flexibility to place applications where they are best suited: in the public cloud for scale and efficiency or at the edge for performance and sovereignty. With this in mind, SD-Core has taken the novel approach of creating a cloud-native solution optimized for multi-cloud, supporting the widest range of edge cloud use cases, and designed to be delivered as-a-service.

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Dual-Mode Control Plane
SD-Core is designed to support the latest 5G capabilities as well as 4G to 5G migration, and this starts with a pre-integrated dual-mode control plane. The SD-Core control plane simultaneously supports 5G standalone (SA), 5G non-standalone (NSA) and 4G/LTE deployments, thus optimizing for flexibility and future-proofing networks.

The SD-Core control plane leverages components of the free5GC and ONF OMEC projects, and builds on this with refactoring to add cloud native capabilities for scale-out, resiliency, multi-cloud agility and SaaS deployment APIs. SD-Core is further structured to allow a single control plane to work with many user plane instances, thus optimizing for edge cloud deployments and for delivering enterprise private 5G from a common core running in the public cloud. 

SD-Core is also instrumented with northbound APIs to support as-a-service deployment models and end-to-end control of slicing and application/service optimization. Furthermore, the APIs allow for private enterprise isolation, providing a multi-tenant mobile core solution for delivering private enterprise 5G as-a-service.

Multiple Distributed User Planes
In addition to the extensive and modular control plane capabilities, SD-Core includes disaggregated user plane components to meet the needs of the most diverse set of deployment scenarios. The User Plane Function (UPF) is the mobile core subsystem that handles application traffic loads, and thus must be placed in the proximity of edge applications to meet the demanding performance requirements of emerging use cases like augmented reality and synchronized industrial robotics.  

SD-Core takes the novel approach of introducing specialized UPFs, each optimized for specific classes of application and each taking advantage of various hardware acceleration options. Deployments can intermix the UPF variants, deploying each where best suited to optimize overall solutions to meet the complete range of edge application demands. SD-Core’s suite of UPFs includes:

  • Maximum performance:
    P4-UPF - a hardware-based dual-mode 4G/5G UPF implemented in the P4 language optimized for high-throughput low-latency applications, with UPF packet processing accelerated by Intel® Tofino™ P4-programmable Ethernet switching silicon ASICs.
  • High throughput on Intel servers:
    DPDK-UPF - a software-based dual-mode 4G/5G UPF, optimized for Intel® Xeon® using DPDK, supporting any I/O option (SR-IOV, AF_PACKET, AF_XDP), and scalable to 100 Gbps on Intel Ethernet Network Adapter E810 with Dynamic Device Personalization (DDP).
  • Maximum flexibility to run on any cloud:
    Flex-UPF - a software-based dual-mode 4G/5G UPF implementation for campus and multi-cloud, implemented with eBPF and optimized with AF_XDP to make it suitable to run on any variety of CPU (to be available later this year).

Enabling a Diversity of 5G Solutions
Operators, solution providers and integrators can combine SD-Core in part or in whole to build comprehensive 5G solutions. SD-Core can be deployed in combination with any commercially available off-the-shelf RAN product (interfacing via the 3GPP S1 interface). In this scenario SD-Core provides a complete mobile core solution, interworking with the integrator’s choice of RAN product(s). 

For those wishing to use components of SD-Core in combination with another proprietary or commercial mobile core offering, SD-Core also exposes standard 3GPP interfaces throughout all internal and external modules. Additionally, SD-Core introduces northbound APIs to support deployment as a cloud-based mobile-core-as-a-service solution (these APIs are leveraged by the Aether platform), and SD-Core is instrumented with a complete CI/CD development environment, supporting agile cloud-native development best practices. This makes SD-Core an ideal platform to augment any 5G solution, supporting 4G-to-5G migration, enterprise private 5G/4G/CBRS, fixed access, virtual mobile operators (MVNOs) and classic mobile operator use cases.

Aether - a Pre-Integrated End-to-End 5G Platform
SD-Core can be leveraged (in whole or in part) as a mobile core platform, but SD-Core is also available pre-integrated in a complete end-to-end private 5G solution. SD-Core is an integral part of Aether, ONF’s Enterprise 5G-Edge-Cloud-as-a-Service platform. Aether simplifies turnkey deployments of private 5G networks for the enterprise, making 5G easy to consume and deploy as a cloud-managed service. Aether’s Runtime Operational Controller (ROC) includes adapters for controlling SD-Core in concert with the end-to-end Aether platform, thus weaving together RAN, fabric and mobile core into a comprehensive offering.

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In summary, SD-Core can be rapidly deployed pre-integrated (with Aether), as a standalone 5G/4G mobile core, or as control and dataplane (UPF) components integrated into custom designed solutions. This range of versatility makes the open source SD-Core platform ideally suited for the broadest range of use cases and deployment scenarios.

Intel is a driving force, a key contributor and a technology provider for the SD-Core project. Intel is contributing capabilities that leverage Intel® Xeon® Scalable Processors and Intel® Software Guard Extensions (Intel SGX) for securing data and control plane functionality.  User plane implementations are also being optimized with Data-Plane Development Kit (DPDK) using Intel® Ethernet 800 Series with Dynamic Device Personalization (DDP) to support 100 Gbps per NIC.  Furthermore, Intel is also collaboratively working with ONF on development of user plane functionality on Intel® Tofino™ P4-programmable Ethernet switch ASICs to serve a spectrum of operator and private 5G use cases.”
Pranav Mehta, Vice President of Systems and Software Research, Intel Labs

Learn More
To learn more, please visit:

The public is invited to attend a live virtual session introducing SD-Core.  Project leaders and technical experts will provide an overview and share insights into the platform, field questions from the community:


About the Open Networking Foundation:
The Open Networking Foundation (ONF) is an operator-led consortium spearheading disruptive network transformation. Now the recognized leader for open source solutions for operators, the ONF first launched in 2011 as the standard bearer for Software Defined Networking (SDN). Led by its operator partners AT&T, China Unicom, Deutsche Telekom, Google, NTT Group and Türk Telekom, the ONF is driving vast transformation across the operator space. For further information visit https://onfstaging1.opennetworking.org