Make Your First Voice Call¶

In this tutorial, we will add Ella IMS to a private 5G network running Ella Core, and make a voice call (VoNR) between two phones.

You can expect to spend about 30 minutes completing this tutorial.

Pre-requisites¶

To complete this tutorial, you will need the following:

Ella Core

A 5G network running Ella Core, as built in Ella Core's Getting Started (5G Network with Radio Hardware) tutorial. In this tutorial, Ella Core's N6 interface, ens3, has the address 10.6.0.2.

Ella IMS

A second Linux machine running Ubuntu 26.04 LTS, on Ella Core's N6 network. In this tutorial, it has the address 10.6.0.5.

Phones

Two 5G phones that support VoNR, each with a SIM provisioned as a subscriber in Ella Core.

1. Enable Diameter in Ella Core¶

On the Ella Core machine, edit the configuration file:

sudo vim /var/snap/ella-core/common/core.yaml

Under interfaces, add the address Ella Core accepts Diameter connections on:

/var/snap/ella-core/common/core.yaml

interfaces:
  diameter:
    address: "10.6.0.2"

Restart Ella Core:

sudo snap restart ella-core.cored

2. Install Ella IMS¶

On the Ella IMS machine, install the Ella IMS snap:

sudo snap install ella-ims
sudo snap connect ella-ims:network-control

Edit the configuration file:

sudo vim /var/snap/ella-ims/common/ims.yaml

Set the address phones reach Ella IMS on, and the address it reaches Ella Core from:

/var/snap/ella-ims/common/ims.yaml

sip:
  addresses: [10.6.0.5]
diameter:
  address: 10.6.0.5

Start Ella IMS:

sudo snap start --enable ella-ims.imsd

Open your browser and navigate to http://10.6.0.5:5020/. You should see Ella IMS's Cores page.

3. Connect Ella IMS to Ella Core¶

Go to the Cores page:

Under Peers, click Add Peer, enter 10.6.0.2, check HSS and PCRF, and click Add.
Under HSS, click the edit icon next to HSS Realm, enter epc.mnc001.mcc001.3gppnetwork.org, and click Update.
Under Voice QoS, click the edit icon next to Policy Function, select PCRF, and click Update.
Click the edit icon next to PCRF Realm, enter epc.mnc001.mcc001.3gppnetwork.org, and click Update.

Under Peers, Ella Core should show as open.

4. Route the phones' traffic¶

On the Ella IMS machine, route the phones' voice addresses, which we create in the next step, through Ella Core:

sudo ip route add 10.46.0.0/16 via 10.6.0.2 mtu lock 1400

5. Prepare Ella Core for voice¶

In the Ella Core UI, go to the Operator page and scroll to the IMS section. Click the edit icon next to P-CSCF Addresses, enter 10.6.0.5, and click Update.

Go to the Networking page and open the Data Networks tab. Click Create, enter ims as the Name, 10.46.0.0/16 as the IPv4 Pool, turn on IMS (voice and mission critical services), and click Create.

Go to the Profiles page and click on the default profile. Click Add Policy, enter voice as the Name, set the Data Network to ims, and click Create.

Go to the Subscribers page. For each of the two subscribers, click on it, click the edit icon next to MSISDN, enter a number, and click Update:

First subscriber: +15551230001
Second subscriber: +15551230002

6. Register the phones¶

On each phone, turn on VoNR, then turn airplane mode on and off.

In Ella IMS, go to the Registrations page. You should see both phones.

7. Make a call¶

From the first phone, call +15551230002. Answer on the second phone, talk, and hang up.

In Ella IMS, go to the Calls page. You should see the call, with the outcome answered.

Success

Congratulations! You have made a voice call over your private 5G network, through Ella Core and Ella IMS.