Why is NID (Network ID) not in EllaCore?

[telecomstimmy14]

Hi, When capturing and analysing network traces from a running 5G Ella Core deployment, the NID (Network ID) field does not appear to be included in the relevant messages, despite being specified in the 3GPP specifications. Per the 3GPP specifications, the NID should be present in network traces to uniquely identify the non-public network (NPN) or a specific network slice/instance. This field is expected to appear alongside the PLMN ID in the relevant protocol messages specifically for SNPNs and not a PNI-NPN deployment.

I was wondering if this was a design consideration around the use of 999 as the MCC, or if it is something that has not been implemented yet. I was expecting to see it within the Registration Accept message, potentially with the Equivalent SNPNs parameter as well.

Thanks,
Tim

[gruyaume]

Hello @telecomstimmy14 ,

Thank you for reaching out.

Can you please pinpoint exactly which specs contradict Ella Core's implementation? Looking at TS 24.501 table 8.2.7.1.1,
NID is not an IE in the Registration Accept message?

And is there a particular reason you care about that field (e.g. "Compatibility issue with device xyz", or "We use that field in our private network deployments for reason xyz") or is it purely an academic concern?

[telecomstimmy14]

Hi @gruyaume thank you for your quick reply, this was just purely academic concern. I think I have found the issue is the disparity in release versions. In R18 I can see the implementation of an Equivalent SNPNs and NID IE within the registration accept. Does this mean EllaCore is aligned to R17? Thanks

[gruyaume]

Ella Core is compatible with Radios and UE's implementing Release 15 and beyond.

It operates using PLMNs rather then the SNPN framework introduced in release 16.

SNPN and NID seem quite relevant for private 5G, but I haven't seen real deployments leveraging that framework yet. If we see demand I'll be happy to prioritise the feature.