How network indicates to UE that cell is ENDC or non ENDC?

Hi NR Experts.

How network indicates to UE that cell is ENDC or non ENDC?
Any message there?
How UE will come to know if we have both LTE and ENDC cell in cluster?

Not an expert but, in SIB2 msg UPPERLAYERIND, if this is ON, UE will know that LTE cell has an upper NR layer.

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LTE SIB2 β†’ PLMN information list β†’ If upper layer IND IE is set a true, then network support ENDC.

Everyone here are Expert :relaxed:

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Of course, upper layer indication isn’t mandatory and without it UE can connect to NR.

Yes, UE can connect with without upper layer indication.

If this indicator is enabled then UE get to know that network is supporting ENDC.

Using that indication UE can display operator specific icon. Example: 5G, 5GUW.

In my view, SIB2 is only for icon display, not to judge cell is ENDC or not.

Is SIB 2 always broadcasted? I think SSB + SIB1 i.e. minimum system information are always broadcasted.

I read somewhere: if NR SIB1 carries TAC information, it is SA. If NR SIB-1 doesnot carry TAC info, it is NSA.

In the case of LTE SIB2 always broadcast.

In the case of NSA, SIB1 is not required only MIB required.

In the case of SA, MiB and SIB1 is always broadcast, and other SIBs broadcast base on operator requirement.

SIB2 always broadcast, but upper layer indication not mandatory.

SIB2 upper layer indication decides cell is EN DC or not.

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As far as I have seen, all documents state 1 thing: that SIB2 Carry 5G NR PLMNs via PLMN info, which tells UE the presence of NR in the network along with LTE.

That’s the trigger point after which UE sends DCNR to n/w on msg3

Presence of New SIBs indicates whether NW is ENDC or not.