HO from 5G to 4G

During EPS fallback, gNB finally sends a HO command to UE or RRC release with redirection message to UE
Please clarify

it is upto NW to decide whether want to use RRC_IDLE or RRC_CONNECTED during EPS Fallback.
RRC_IDLE use by 5G RAN : RRCRelease with EUTRAN Freq
RRC_CONNECTED : Handovercommand wirth Target cell as EUTRA


If 5G UE in Active session then it will use HO Command
If not …assume in Idle then RRC Release with Redirect.

Even in CONNECTED , NW can send RRCRelease woth redirection info.
it is upto the NW to decide

Usually this kind of transition is done by Redirection in order to save time and resources.

1 Like