I’m seeing in SA log UE capability enquiry RAT type as NR.
I mean only this field present for SA site.
I think we can say so.
Yes, this is my gut feeling.
Will do a DT to check this anyway.
Basically we don’t want to spent on SA license now to identify SA presence.
Hold on.
Difference is that UE capability enquiry in 5G SA will be sent over 5G RRC.
In NSA will be sent over 4G RRC.
Ooops, then it cannot be done. 
In NSA we always seen 2 field in UE capability enquiry, i.e. RAT type as NR and eUTRA-NR.
Without SA license you will not see any 5G RRC message.
Yes, me too.
We have 2 UE capability enquiry in NSA one for RAT type as eutra, utra.
Other for RAT type as eutra-nr, nr.
In SA logs UE capability enquiry single message only with rat type as NR.
Yes, once in LTE n/w then the second one.
One more diff non critical extension part of UE capability enquiry i.e. eutra-nr-only-r15 is true for NSA.
This field absent in SA logs.
Yes it is for MRDC/ENDC I think.
Yes, correct.
So I think I cannot detect SA presence using NSA device, but still will look into any Mobility identifiers from LTE to 5G SA to capture this.
Why in NSA we don’t see SIB1?
Because there is no need for it or for any other SIB.
Everything comes via RRC con reconfig in 4G.
Agree, SIB1 needed for ANR, but current devices not support ANR.
So you can save SIB1 CCE to improve your TP.
NSA devices can detect SSB and read the contents of PBCH/MIB. If kSSB > 23, this cell does provide SA service
No SIB1 in NSA for 5G, but I got an IE from MIB in NSA/SA which tends to give me the SA indication.
As per my observation :
pdcch-ConfigSIB1- 255 in NSA
pdcch-ConfigSIB1- some other value say 114
There is pdcch-configsib1 in both SA and NSA.
Just that in NSA is not taken into account.