5G CORE NETWORK

The goal of the OAI-5G Core Network (CN) project group is to provide a 3GPP-Compliant 5G Standalone (SA) CN implementation with a rich feature set. OAI 5G CN is designed and implemented in a flexible way which can be easily adapted to fulfill the needs of diversified 5G use-cases. All the features of the OAI 5G CN components are continuously tested with professional testers, commercial gNBs (with COTS UE) and open-source RAN simulators.  

All the OAI 5G CN components are published under the OAI Public License V1.1. 

5G CN Overview

In order to support a very diverse range of services envisioned for 5G with very different performance requirements, 5GC is designed with a service-oriented architecture through the adoption of the new 3GPP defined service-based architecture (SBA). In this architecture, a set of 5GC components, or in this case called Network Functions (NFs) provide services to others authorized NFs to access their services. For the interaction between network functions, one of these acts as a Service Consumer, and the other as a Service Producer. Additionally, the Control Plane (CP) functions are separated from the User Plane (UP) in order to make them scaling independently, allowing operators to use these components for dimensioning, deploying and adapting the network to their needs easily. Figure 1 depicts the non-roaming reference architecture for 5GC. For more details, please refer to 3GPP TS 23.501.  

Figure 1. non-roaming reference architecture for 5GC (TS 23.501)

OAI 5G CN – Current status

The OAI 5G CN project plans to have a full standalone 3GPP-compliant 5G CN implementation (as described in Figure 1). In release v1.4.0, we implemented the following Network Functions (NF): 

OAI 5G CN implementation has been extensively tested and validated with: 

Features

Currently, OAI 5G CN supports basic procedures for connection, registration (UE registration, de-registration, and service request) and session management (PDU session establishment, modification and release). OAI 5G CN also supports some additional features e.g., N2 Handover, HTTP/2, FQDN support, Paging, Network slicing (partially supported). It is worth mentioning that OAI 5G CN can support multiple UEs and multiple PDU sessions at the same time (please refer to this tutorial for more information). 

OAI 5G CN can be adapted to support different use-case scenarios with different deployment options and different flavors for the User Plane.

Three deployment modes: 

1) Minimalist 5GC with AMF, SMF, NRF, and UPF 
2) Basic 5GC with AMF, SMF, NRF, UPF, UDM, AUSF and UDR
3) Slicing 5GC with AMF, SMF, NRF, UPF, UDM, AUSF, UDR, and NSSF 

Three UPF flavors: 

1) SPGW-U-tiny (from 4G) with additional features for 5G 
2) VPP-UPF (relying on VPP-Travelping, with DPDK support)

3) Production grade UPF (SD-Fabric, on-going)

Three deployment platforms: 

1) Bare-metal installation or in virtual machines
2) Automated deployment of NFs in Docker containers using Docker-Compose
3) Cloud-native deployment using Helm Chart (on OpenShift/Kubernetes cluster)

OAI 5G CN PG Roadmap – Revisited March 2022

The OAI community is invited to refer to the following roadmap that gives the sequencing and the timeline for the availability of different functions of a 3GPP compliant 5G core. The roadmap roughly spans four quarters. We shall regularly keep revisiting the roadmap to give the OAI community constant visibility over a similar timeframe.

PROJECT GROUP SPONSORSHIP MECHANISM

To accelerate the development and delivery of 5G components, the OSA launched a new sponsorship mechanism called PROJECT GROUP in Q1 2021 for its partners, especially the industry, who are invited to donate financial resources to developments through these PROJECT GROUPS. The OAI 5G CN PROJECT GROUP has the goal of developing a 3GPP compliant 5G Core Network (CN) stack as open-source software for the OAI community. The software is distributed under the OAI Public License V1.1.

Parties seriously interested in leveraging the OAI 5G CN code for their use-cases and thus looking to influence the development roadmap can participate by joining the Alliance as Strategic Members and then participating in the OAI 5G CN PROJECT GROUP in one of the donor categories. For more details on the working of the Project Group and sponsorship categories, please download the Project Group Charter.

For inquiries on how to participate in the OAI 5G CN PROJECT GROUP, please write to: contact@openairinterface.org

Project Code

Please visit the home of the project on Gitlab