O-RAN xApps Closed-Loop Control Using DRL-Based RAN Slicing

Team Members

• Soham Sitapara (202251131)
• Sudhanshu Bharti (202251134)
• Vasani Om (202251154)
• Ishan Raj (202251174)

Project Description

This project explores the implementation and analysis of Open Radio Access Network (O-RAN) using the *ns-O-RAN simulation platform. The focus is on integrating *Near-RT RIC and Non-RT RIC components with custom xApps to enable closed-loop control for 5G networks. The study employs mmWave technology and E2 termination to achieve real-time communication between RAN components, emphasizing:

• Network optimization
• Resource management
• Low latency and high reliability

The project demonstrates the practical viability of O-RAN architecture and highlights its advantages over traditional RAN solutions, such as:

• Vendor neutrality
• Modularity and flexibility
• Integration of AI/ML solutions for dynamic resource allocation

Key Components

• *ns-3 Integration: Utilizes the *ns3-mmWave version and ns-O-RAN module for detailed 5G simulations.
• E2 Interface: Supports real-time communication between RIC and RAN components.
• RIC and xApp Setup: Implements xApps for control logic and performance optimization.
• Closed-Loop Control: Simulates traffic steering and mobility management using E2 Service Models.

Hardware and Software Description

Simulation Environment

• e2term Terminal: Logs E2AP interactions for diagnostics and monitoring.
• xApp Terminal: Executes custom xApps for dynamic optimization.
• ns-o-ran Terminal: Integrates ns-3 with RIC components for seamless simulation.

System Configuration

• Central eNB: LTE-based central node.
• Four gNBs: Positioned at 1000m apart, connected via the ns-3 environment.

Step-by-Step Setup Guide

1. Near-RT RIC Setup

This part of the tutorial requires a working version of Docker for hosting the RIC on your localhost.

Step 1.1: Clone and Setup the Colosseum's Near-RT RIC

bash git clone -b ns-o-ran https://github.com/wineslab/colosseum-near-rt-ric cd colosseum-near-rt-ric/setup-scripts

Step 1.2: Import Docker Images and Launch RIC

bash ./import-wines-images.sh # import and tag ./setup-ric-bronze.sh # setup and launch

Step 1.3: Verify RIC Setup

Check if the main entities of the RIC are up and running using: bash docker ps

Step 1.4: Logging and xApp Setup

Open two terminals for the RIC:

• Terminal 1: Logs the E2Term bash docker logs e2term -f --since=1s 2>&1 | grep gnb:

• Terminal 2: Builds and runs the xApp container bash cd colosseum-near-rt-ric/setup-scripts ./start-xapp-ns-o-ran.sh

Step 1.5: Run the xApp Logic

Inside the Docker container, navigate to the xApp directory and run the xApp: bash cd /home/sample-xapp ./run_xapp.sh

2. ns-O-RAN Setup

Step 2.1: Install Prerequisites

In Ubuntu 20.04 LTS, install the necessary packages: bash sudo apt-get update

Requirements for e2sim

sudo apt-get install -y build-essential git cmake libsctp-dev autoconf automake libtool bison flex libboost-all-dev

Requirements for ns-3

sudo apt-get install g++ python3

Step 2.2: Clone and Install e2Sim Software

bash git clone https://github.com/wineslab/ns-o-ran-e2-sim oran-e2sim cd oran-e2sim/e2sim/ mkdir build ./build_e2sim.sh 3

Step 2.3: Clone and Install ns3-mmWave Project

bash git clone https://github.com/wineslab/ns-o-ran-ns3-mmwave ns-3-mmwave-oran cd ns-3-mmwave-oran

Step 2.4: Clone ns-O-RAN Module

bash cd ns-3-mmwave-oran/contrib git clone -b master https://github.com/o-ran-sc/sim-ns3-o-ran-e2 oran-interface cd .. # go back to the ns-3-mmwave-oran folder

Step 2.5: Configure and Build ns-3

bash ./waf configure --enable-examples --enable-tests ./waf build

3. Running the Simulation

Step 3.1: Run Scenario Zero

bash ./waf --run scratch/scenario-zero.cc

Step 3.2: Verify Message Flow

Ensure the following messages flow between ns-3 and the RIC:

1. E2 Setup Request (ns-O-RAN to E2 Term on RIC)
2. E2 Setup Response (E2 Term on RIC to ns-O-RAN)
3. E2 Subscription Request (xApp to ns-O-RAN through E2 Term on RIC)
4. E2 Subscription Response (ns-O-RAN to xApp through E2 Term on RIC)
5. E2SM RIC Indication Message (ns-O-RAN to xApp through E2 Term on RIC)

Contributions and Acknowledgment

We acknowledge the guidance and support of Dr. Bhupendra Kumar and the resources provided by IIIT Vadodara, which were instrumental in the success of this project.

References

• ns-O-RAN Paper: Programmable and Customized Intelligence for Traffic Steering in 5G Networks Using Open RAN Architectures
• GitHub Repositories:
  • ns-O-RAN
  • Colosseum Near-RT RIC