ORANSlice is an end-to-end open-source 5G network slicing framework for O-RAN. It (i) extends the 5G protocol stacks of OAI to support RAN slicing; (ii) implements an E2SM-CCC-based SM and xApp for RAN slicing control; (iii) conducts extensive testing and validation on Arena and X5G testbeds to ensure the robustness and effectiveness of the implementation.

More details can be found in the ORANSlice GitHub repository and in the following paper:

H. Cheng, S. D’Oro, R. Gangula, S. Velumani, D. Villa, L. Bonati, M. Polese, T. Melodia, G. Arrobo, C. Maciocco, "ORANSlice: An Open Source 5G Network Slicing Platform for O-RAN," in Proceedings of ACM Workshop on Open AI and Open RAN (Open AI RAN), Washington, D.C., USA, November 2024. [pdf] [bibtex]

Deployment Tutorial

The end-to-end 5G network slicing framework consists of three components: Core Network (CN), Radio Access Network (RAN), and Near-Real-Time RAN Intelligent Controller (Near-RT RIC). The ORANSlice repository includes the code for OAI RAN and OAI CN, while the Near-RT RIC resides in separate repositories. In this tutorial, we will demonstrate how to deploy all three components on Ubuntu 22.04.

git clone https://github.com/wineslab/ORANSlice.git

5G Core Network Slicing

We provide OAI and Open5GS core network slicing deployment in docker.

OAI Core

Deploy OAI core legacy version (v1.5.1) or latest version (develop branch) from the oai_cn directory. A more indepth guide is present in the README.md.

Open5GS

The code for deploying the Open5GS CN in Docker is available in the following GitHub repository.

5G RAN Slicing

The RAN Slicing implementation is based on the OAI 5G protocol stack.

OAI monolithic gNB

Install protobuf-c for E2Agent

sudo apt-get update
sudo apt install protobuf-compiler
sudo apt install libprotoc-dev
git clone https://github.com/protobuf-c/protobuf-c && cd protobuf-c/ && ./autogen.sh && ./configure && make && sudo make install && sudo ldconfig

Go to oai_ran folder and follow these steps.

Build OAI gNB

cd cmake_targets
./build_oai -I
./build_oai -w USRP --ninja --gNB

The customized RAN slicing and E2 Agent code have been integrated into the OAI 2024.w28 release.

Disaggregated gNB from NVIDIA Aerial and OAI

Please refer to the tutorial in ARC-OTA and Aerial CUDA-Accelerated RAN.

OAI nrUE with Multiple-PDU Support

Our customized OAI nrUE with multiple-PDU support is available at:

https://gitlab.eurecom.fr/oai/openairinterface5g/-/tree/NR_UE_multi_pdu

Follow the official guide to build and run the OAI nrUE.

Refer to the configuration guide to set up multiple PDU sessions on the nrUE.

If you do not need multiple-pdu support at nrUE, you can build and run nrUE at oai_ran

COTS UE

You can use COTS 5G UE modules from Sierra Wireless or Quectel to establish a network slicing connection.

Near-Real-Time RIC

OSC Near-RT RIC

The O-RAN Software Community (OSC) Near-RT RIC Release E can be installed following this guide. Note that, for this tutorial, the OSC Near-RT RIC runs on an OpenShift cluster, whereas a plain Kubernetes deployment might require specific networking configurations.

E2Sim

The e2sim is a component that can run on the same server as the gNB and has the duty to encapsulate/decapsulate the custom Service Model (SM) buffers to be sent to or received from the gNB. It communicates with the gNB via UDP sockets. The e2sim codebase is available in this GitHub repository.

xApp

Our xApp consists of two components: a C/C++ based xApp Base Station (BS) Connector and a python-based xApp logic unit. The code is available in the following GitHub repository.

xApp BS Connector

The xApp BS Connector component links the Pythonic xApp with the OSC Near-RT RIC. On one end, it receives custom SM buffers, encapsulates them in E2AP (E2 Application Protocol) messages, and sends them to the RIC. On the other end, it extracts custom SM buffers from E2AP and forwards them to the xApp.

xApp logic unit

The xApp logic unit includes Python examples that subscribe to selected RAN parameters, receive periodic indication messages, and send control requests to update these parameters.

Run a 5G Network Slicing System based on ORANSlice

We provide a step-by-step example demonstrating how ORANSlice works using fully softwarized 5G Open RAN components.

Legacy OAI core network

cd ~/ORANSlice/oai_cn/oai-cn5g-legacy/
./restart_cn.sh

OAI gNB

RFSim mode:

cd ~/ORANSlice/oai_ran/cmake_targets/ran_build/build 
sudo ./nr-softmodem -O ../../../targets/PROJECTS/GENERIC-NR-5GC/CONF/ORANSlice.gnb.sa.band78.fr1.106PRB.usrpx310.conf --sa  --rfsim

Over-the-Air Transmission with USRP X310:

cd ~/ORANSlice/oai_ran/cmake_targets/ran_build/build 
sudo ./nr-softmodem -O ../../../targets/PROJECTS/GENERIC-NR-5GC/CONF/ORANSlice.gnb.sa.band78.fr1.106PRB.usrpx310.conf --sa --usrp-tx-thread-config 1

OAI nrUE

RFSim mode:

sudo ./nr-uesoftmodem -r 106 --numerology 1 --band 78 -C 3619200000 --sa -O ../../../targets/PROJECTS/GENERIC-NR-5GC/CONF/nrUE_slice1.conf --rfsim --rfsimulator.serveraddr 127.0.0.1

OTA Transmission with USRP B210:

sudo ./nr-uesoftmodem -r 106 --numerology 1 --band 78 -C 3619200000  --sa  -O ../../../targets/PROJECTS/GENERIC-NR-5GC/CONF/nrUE_slice1.conf --ue-fo-compensation -E

OTA Transmission with USRP X310:

sudo ./nr-uesoftmodem -r 106 --numerology 1 --band 78 -C 3619200000  --sa  -O ../../../targets/PROJECTS/GENERIC-NR-5GC/CONF/nrUE_slice1.conf --ue-fo-compensation --usrp-args "addr=192.168.40.2"

Modify the IMSI/NSSAI/DNN items of nrUE_slice1.conf to setup another OAI nrUE. For example, nrUE_slice2.conf.

E2Sim

cd o-ran-e2sim
./run_e2sim.sh <e2term-address> <e2term-port>

xAPP

xApp BS Connector

cd xapp_bs_connector
./run_xapp.sh

Wait for the connector to complete its initialization, indicated by messages such as:

Opened control socket server on port 7000

xApp Logic Unit

cd base-xapp
python slicing_ctrl_influxdb_xapp_kpm.py

Others

The kpm-xapp.py script can be easily modified to store these metrics in an external database, such as InfluxDB, and visualize them on a dashboard, such as Grafana.

Troubleshooting

RAN Slicing functionality

You can test the RAN Slicing functionality without the xApp and Near-RT RIC by applying the following patch:

cd oai_ran
git apply ../doc/rrmPolicyJson.patch

After applying the patch, a file named rrmPolicy.json is added to the root folder of ORANSlice. The MAC layer will then periodically read rrmPolicy.json to update the internal slicing policy.

Accordingly, you need to set

SliceConf = “/home/wineslab/ORANSlice/rrmPolicy.json”;

in MACRLCs of ORANSlice.gnb.sa.band78.fr1.106PRB.usrpx310.conf to the correct path of rrmPolicy.json.

Adjust the values of min_ratio and max_ratio to observe the throughput changes in each slice.