UERANSIM Deployment Guide

Network Setup

SD-Core VM Preparation

To Expose External IP and Port of amf service, update sd-core-5g-values.yaml

amf:
  # use externalIP if you need to access your AMF from remote setup and you don't
  # want setup NodePort Service Type
  ngapp:
    externalIp: 10.10.1.1 #ip address of DATA_IFACE
    port: 38412

Deploy 5g core with options DATA_IFACE=ens1f0 and ENABLE_GNBSIM=false, sample command:
```
$ ENABLE_GNBSIM=false DATA_IFACE=ens1f0 CHARTS=release-2.0 make 5g-core
```
Make sure that DATA_IFACE connected with UERANSIM VM

UERANSIM VM Preparation

Single interface is used for user plane traffic towards UPF and also control plane traffic towards AMF
Add following route in routing table for sending traffic over DATA_IFACE interface
```
$ ip route add 192.168.252.3 via 10.10.1.1
```

Changes done on UERANSIM to match config with above network topology:

diff --git a/config/free5gc-gnb.yaml b/config/free5gc-gnb.yaml
index 81bb13b..452ccad 100644
--- a/config/free5gc-gnb.yaml
+++ b/config/free5gc-gnb.yaml
@@ -5,13 +5,13 @@ nci: '0x000000010'  # NR Cell Identity (36-bit)
 idLength: 32        # NR gNB ID length in bits [22...32]
 tac: 1              # Tracking Area Code

-linkIp: 127.0.0.1   # gNB's local IP address for Radio Link Simulation (Usually same with local IP)
-ngapIp: 127.0.0.1   # gNB's local IP address for N2 Interface (Usually same with local IP)
-gtpIp: 127.0.0.1    # gNB's local IP address for N3 Interface (Usually same with local IP)
+linkIp: 10.10.1.2   # gNB's local IP address for Radio Link Simulation (Usually same with local IP)
+ngapIp: 10.10.1.2   # gNB's local IP address for N2 Interface (Usually same with local IP)
+gtpIp: 10.10.1.2    # gNB's local IP address for N3 Interface (Usually same with local IP)

 # List of AMF address information
 amfConfigs:
-  - address: 127.0.0.1
+  - address: 10.10.1.1
     port: 38412

 # List of supported S-NSSAIs by this gNB
diff --git a/config/free5gc-ue.yaml b/config/free5gc-ue.yaml
index 9089ba0..aa0df2e 100644
--- a/config/free5gc-ue.yaml
+++ b/config/free5gc-ue.yaml
@@ -1,14 +1,14 @@
 # IMSI number of the UE. IMSI = [MCC|MNC|MSISDN] (In total 15 digits)
-supi: 'imsi-208930000000003'
+supi: 'imsi-208930100007509'
 # Mobile Country Code value of HPLMN
 mcc: '208'
 # Mobile Network Code value of HPLMN (2 or 3 digits)
 mnc: '93'

 # Permanent subscription key
-key: '8baf473f2f8fd09487cccbd7097c6862'
+key: '5122250214c33e723a5dd523fc145fc0'
 # Operator code (OP or OPC) of the UE
-op: '8e27b6af0e692e750f32667a3b14605d'
+op: '981d464c7c52eb6e5036234984ad0bcf'
 # This value specifies the OP type and it can be either 'OP' or 'OPC'
 opType: 'OPC'
 # Authentication Management Field (AMF) value
@@ -20,7 +20,7 @@ imeiSv: '4370816125816151'

 # List of gNB IP addresses for Radio Link Simulation
 gnbSearchList:
-  - 127.0.0.1
+  - 10.10.1.2

 # UAC Access Identities Configuration
 uacAic:
@@ -57,14 +57,14 @@ default-nssai:
 # Supported integrity algorithms by this UE
 integrity:
   IA1: true
-  IA2: true
-  IA3: true
+  IA2: false
+  IA3: false

 # Supported encryption algorithms by this UE
 ciphering:
-  EA1: true
-  EA2: true
-  EA3: true
+  EA1: false
+  EA2: false
+  EA3: false

 # Integrity protection maximum data rate for user plane
 integrityMaxRate:

Once UE is connected to 5G NetwChanges done on UERANSIM to match config with above network topology:

node1:~ ifconfig uesimtun0

uesimtun0: flags=369<UP,POINTOPOINT,NOTRAILERS,RUNNING,PROMISC>  mtu 1400
        inet 172.250.237.124  netmask 255.255.255.255  destination 172.250.237.124
        inet6 fe80::2697:29c8:d043:cf35  prefixlen 64  scopeid 0x20<link>
        unspec 00-00-00-00-00-00-00-00-00-00-00-00-00-00-00-00  txqueuelen 500  (UNSPEC)
        RX packets 16  bytes 1344 (1.3 KB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 558  bytes 46516 (46.5 KB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

node1:~$ ping -I uesimtun0 8.8.8.8
PING 8.8.8.8 (8.8.8.8) from 172.250.237.124 uesimtun0: 56(84) bytes of data.
64 bytes from 8.8.8.8: icmp_seq=1 ttl=111 time=14.4 ms
64 bytes from 8.8.8.8: icmp_seq=2 ttl=111 time=14.4 ms
^C
--- 8.8.8.8 ping statistics ---
2 packets transmitted, 2 received, 0% packet loss, time 1002ms
rtt min/avg/max/mdev = 14.377/14.380/14.384/0.003 ms
node1:~$

Note

In above network topology, SD-Core node has iptables NAT rule applied so that UE traffic is NATed and reverse traffic is sent to UERANSIM.

iptables -t nat -A POSTROUTING -o eno34 -j MASQUERADE