VoNR setup - Call ended issue

[Borjis131]

ims_logs.zip

Hi Supreeth, Borja here from the neighbour project docker-open5gs 😄

I am trying your sa-vonr-deploy.yaml Docker Compose deployment to learn a bit about VoNR and IMS. But I am having an issue, after following your README.md steps and testing the Internet connection through the internet DNN, when trying to call a UE the UE displays "call ended" immediately and I do not know how to debug from here, due to my lack of VoNR/IMS experience.

The setup is the following:
Your sa-vonr-deploy.yaml Docker Compose file out of the box with only the following changes:

• Using your ghcr.io/herlesupreeth/:master Docker images
• PLMN 001-01
• SST: 1, SD: 010203
• AMF and UPF exposing ports to connect to an external gNB
• gNB is a LiteON FlexFi AIO
• UEs are Zebra TC58

After connecting the UEs, the connection was tested using the Ookla SpeedTest. After that I tried to call from both sides using the MSISDN configured and their respective IMSI with the very same results ("call ended").

Phones have 5G as preferred connectivity as well as VoLTE enabled (I can't see a different one for VoNR so I guess from the UE's perspective both are the same, just IMS).

I can see through the logs, that a different PDU Session to the DNN ims are being setup, but that is as far as I can see.

Find attached in the WeTransfer link (7 days expires, tell me if you need it after):

• ims.pcap: PCAP file of the Docker bridge
• webui and pyhss configuration
• Most relevant log files, I couldn't attach the full S-CSCF log

https://we.tl/t-LUeYc9DUFv

Attached in the WeTransfer link because the PCAP is too big (1.2 GB, due to the SpeedTest traffic).

Find also attached a slim version (I hope I did not remove something relevant)

Thanks in advance 🤗

[herlesupreeth]

@Borjis131 Hey Borja, nice to see you here :)

I had a look at the pcap and the log file, I see that 2 UEs registered with IMS (all good here) but I dont see any SIP invite neither in pcap nor in P-CSCF logs

Can you please ensure you are typing in the correct MSISDN without + at the start and also not dialing self?

[Borjis131]

Hi Supreeth, thank you for your quick response.

You are right, I can see the SIP REGISTER but no more than that.

I won't be able to show you captures of how I did it today, but I can tell you that I tried typing:
From UE 1 (IMSI: 001011234567891 and MSISDN: 9076543201) calling to 9076543202, to IMSI 001011234567892 and to itself (9076543201 and IMSI 001011234567891).

And the other way around, starting from UE 2 and calling MSISDN of UE 1, IMSI of UE 1, MSISDN of UE2 and IMSI of UE 2.

All of them getting the same result: Call ended immediately.

I don't know if my PLMN selection could be affecting this test, did you find any issue using VoNR + PLMN 001-01? Asking ChatGPT says it could be something related to the MBN files of the phone not having IMS configured for this carrier.

What are your thoughts about this? Thanks a lot

[herlesupreeth]

I don't know if my PLMN selection could be affecting this test, did you find any issue using VoNR + PLMN 001-01?

One difference in my usage to yours is that I dont use Slicing related parameters i.e. SST 1 but SD unconfigured

[Borjis131]

Ok, I can try leaving the SD unset too but I thought having tested the DNN registration for both internet and ims should be enough to clarify there is no issue on the 5G configuration side.

[herlesupreeth]

If I may ask, can you please let me know how you managed to get the UE to request a particular Slice with SD value set towards the network?

[Borjis131]

Hi Supreeth, sorry for taking so long. I did not have access to the lab until today.

I send you the ouput of the phones when executing the *#*#4636#*#* hidden menu (4636_menu_ue pics), also the dial menu showing that I have tried to call (calls_ue pics) and a screen recording of doing the full process (Screen-Recording.mp4 file).

ims_logs_2.zip

Regarding your question:
From my experience, you only have to configure slicing into the gNB and 5G Core. It is not like in UERANSIM where you need to add the S-NSSAI parameters into the UE too. With that, the UE selects the S-NSSAI by itself.

[herlesupreeth]

@Borjis131 Thanks for the screen recording. I couldn't find any issues. One thing you could try is putting the phone in safe mode and restarting normally. After that you can give it a try once more to see if the issue persists

From my experience, you only have to configure slicing into the gNB and 5G Core.

Interesting since I couldnt get it to work with just configuring slice information on srsRAN_Project gNB + core. The UE would simply not send slice selection information in the initial register message to the Core. I was under the impression that one needed to program the EF.URSP field in the SIM so that UE can make use of that while registering with the network

[Borjis131]

Hi @herlesupreeth, thanks a lot for the help. I will try it as soon as possible.

I have also extracted logs from the radio of the phone using adb, I can share them if you want to take a look to see if there are more clues. I extracted logs while the phone was attaching to the network and also while trying to call.

Interesting since I couldnt get it to work with just configuring slice information on srsRAN_Project gNB + core. The UE would simply not send slice selection information in the initial register message to the Core. I was under the impression that one needed to program the EF.URSP field in the SIM so that UE can make use of that while registering with the network

I have always done it that way and it worked perfectly using multiple UEs (Samsung S21+, S23, iPhones, OnePlus and even 5G modems based on Quectel). But each phone has its own things, so I don't really know why it did not worked in your case I can only suggest you to try it again with a different one if you have access.

I haven't tried setting the URSP fields on Android apps nor the SIM card details.