Table of Contents

• Hardware Tested
• Questions
• Recommended Environment
• Installation
  • A. Prerequisites
  • B. Install Control Plane Elements
  • C. Install User Plane Function (UPF)
• Run
  • A. Run the Core Network
  • B. Run the N3IWF (Individually)
  • C. Run all-in-one with outside RAN
  • D. Deploy within containers
• Test
• More information
• Release Note

Hardware Tested

In the market today, there are neither hardware gNB nor hardware UEs that interface directly with a standalone 5GC, so no hardware testing has yet been performed against free5gc.

Questions

For questions and support please use the official forum. The issue list of this repo is exclusively for bug reports and feature requests.

Recommended Environment

free5gc has been tested against the following environment:

• Software
  • OS: Ubuntu 18.04
  • gcc 7.3.0
  • Go 1.14.4 linux/amd64
  • kernel version 5.0.0-23-generic

The listed kernel version is required for the UPF element.

• Minimum Hardware

  • CPU: Intel i5 processor
  • RAM: 4GB
  • Hard drive: 160GB
  • NIC: Any 1Gbps Ethernet card supported in the Linux kernel

• Recommended Hardware

  • CPU: Intel i7 processor
  • RAM: 8GB
  • Hard drive: 160GB
  • NIC: Any 10Gbps Ethernet card supported in the Linux kernel

This guide assumes that you will run all 5GC elements on a single machine.

Installation

A. Prerequisites

1. Linux Kernel Version

   • In order to use the UPF element, you must use the 5.0.0-23-generic version of the Linux kernel. free5gc uses the gtp5g kernel module, which has been tested and compiled against that kernel version only. To determine the version of the Linux kernel you are using:

       $ uname -r
       5.0.0-23-generic

You will not be able to run most of the tests in Test section unless you deploy a UPF.

2. Golang Version

   • As noted above, free5gc is built and tested with Go 1.14.4
   • To check the version of Go on your system, from a command prompt:

       go version

   • If another version of Go is installed, remove the existing version and install Go 1.14.4:

       # this assumes your current version of Go is in the default location
       sudo rm -rf /usr/local/go
       wget https://dl.google.com/go/go1.14.4.linux-amd64.tar.gz
       sudo tar -C /usr/local -zxvf go1.14.4.linux-amd64.tar.gz

   • If Go is not installed on your system:

       wget https://dl.google.com/go/go1.14.4.linux-amd64.tar.gz
       sudo tar -C /usr/local -zxvf go1.14.4.linux-amd64.tar.gz
       mkdir -p ~/go/{bin,pkg,src}
       # The following assume that your shell is bash
       echo 'export GOPATH=$HOME/go' >> ~/.bashrc
       echo 'export GOROOT=/usr/local/go' >> ~/.bashrc
       echo 'export PATH=$PATH:$GOPATH/bin:$GOROOT/bin' >> ~/.bashrc
       source ~/.bashrc

   • Further information and installation instructions for golang are available at the official golang site.

3. Control-plane Supporting Pacakges

sudo apt -y update
sudo apt -y install mongodb wget git
sudo systemctl start mongodb

4. User-plane Supporting Packages

sudo apt -y update
sudo apt -y install git gcc cmake autoconf libtool pkg-config libmnl-dev libyaml-dev
go get -u github.com/sirupsen/logrus

5. Linux Host Network Settings

sudo sysctl -w net.ipv4.ip_forward=1
sudo iptables -t nat -A POSTROUTING -o <dn_interface> -j MASQUERADE
sudo systemctl stop ufw

B. Install Control Plane Elements

1. Clone the free5GC repository

   • To install the latest stable build (v3.0.4):

       cd ~
       git clone --recursive -b v3.0.4 -j `nproc` https://github.com/free5gc/free5gc.git
       cd free5gc

   • Alternatively, if you wish to install the latest nightly build:

       cd ~/free5gc
       git checkout master
       git submodule sync
       git submodule update --init --jobs `nproc`
       git submodule foreach git checkout master
       git submodule foreach git pull --jobs `nproc`

2. Install all Go module dependencies

cd ~/free5gc
go mod download

NOTE: the root folder name for this repository must be free5gc. If it is changed, compilation will fail.

3. Compile network function services in free5gc

   • To do so individually (e.g., AMF only):

       cd ~/free5gc
       make amf

   • To build all network functions:

       cd ~/free5gc
       make all

C. Install User Plane Function (UPF)

1. As noted above, the GTP kernel module used by the UPF requires that you use Linux kernel version 5.0.0-23-generic. To verify your version:

uname -r

2. Retrieve the 5G GTP-U kernel module using git and build it

git clone -b v0.2.0 https://github.com/PrinzOwO/gtp5g.git
cd gtp5g
make
sudo make install

3. Build the UPF (you may skip this step if you built all network functions above):

   a. to build using make:

   cd ~/free5gc
   make upf

   b. alternatively, to build manually:

   cd ~/free5gc/src/upf
   mkdir build
   cd build
   cmake ..
   make -j`nproc`

4. Customize the UPF as desired. The UPF configuration file is free5gc/src/upf/build/config/upfcfg.yaml.

Run

A. Run the Core Network

Option 1. Run network function services individually. For example, to run the AMF:

cd ~/free5gc
./bin/amf

Note: The N3IWF needs specific configuration, which is detailed in section B.

Option 2. Run whole core network

cd ~/free5gc
./run.sh

B. Run the N3IWF (Individually)

To run an instance of the N3IWF, make sure your system is equipped with three network interfaces: the first connects to the AMF, the second connects to the UPF, and the third is for IKE daemon.

Configure each interface with a suitable IP address.

Create an interface for IPSec traffic:

# replace <...> to suitable value
sudo ip link add ipsec0 type vti local <IKEBindAddress> remote 0.0.0.0 key <IPSecInterfaceMark>

Assign an address to this interface, then bring it up:

# replace <...> to suitable value
sudo ip address add <IPSecInterfaceAddress/CIDRPrefix> dev ipsec0
sudo ip link set dev ipsec0 up

Run the N3IWF (root privilege is required):

cd ~/free5gc/
sudo ./bin/n3iwf

C. Run all-in-one with external RAN

Refer to this sample config if you wish to connect an external RAN with a complete free5GC core network.

D. Deploy within containers

free5gc-compose provides a sample for the deployment of elements within containers.

Test

Start a Wireshark capture on any core-connected interface, applying the filter 'pfcp||icmp||gtp'.

In order to run the tests, first do this:

cd ~/free5gc
chmod +x ./test.sh

The tests are all run from within ~/free5gc.

a. TestRegistration

./test.sh TestRegistration

b. TestGUTIRegistration

./test.sh TestGUTIRegistration

c. TestServiceRequest

./test.sh TestServiceRequest

d. TestXnHandover

./test.sh TestXnHandover

e. TestDeregistration

./test.sh TestDeregistration

f. TestPDUSessionReleaseRequest

./test.sh TestPDUSessionReleaseRequest

g. TestPaging

./test.sh TestPaging

h. TestN2Handover

./test.sh TestN2Handover

i. TestNon3GPP

./test.sh TestNon3GPP

j. TestReSynchronisation

./test.sh TestReSynchronisation

k. TestULCL

./test_ulcl.sh -om 3 TestRegistration

More information

For more details, reference the free5gc wiki.

Release Note

Detailed changes for each release are documented in the release notes.