Hello.
What is use of I-RNTI in 5G SA?
Newly introduced RNTI having 2 types - Full IRNTI 40bit and short IRNTI 24 bits.
In layman’s language, if signal is good and UE has enough resources then Full IRNTI is used else Short IRNTI.
Its actual flag is transmitted inside SIB1.
It’s linked with RRC inactive state in NR.
Yes, its the part of RRC release → suspect config.
Suspend config info IE in rrc release
From network end we have inactivity timer present in SA as well like lte seen.
Value like 5,10 s can be configurable.
Yes inside that full & short irnti info is sent towards UE.
But which one ue has to use is figured out from SIB1 → Use Full Resume ID = TRUE.