Which node of lte network initiate CSFB ?

Question

If UE doesn't have any PS session and any CSFB call initiated then UE redirected to WCDMA or GSM and after ending CS session UE moved to LTE network by performing Tracking area update.

But in case PS session is on going and CS call have to be initiated then Handover to WCDMA will be performed. But when CS call finished and PS session is also still ongoing then which procedure will be performed to move again LTE Network? If its Handover then how measurement reporting will be done.

Answer 1

Its the MME which initiate the CSFB. When UE sends the "exended service request" message with CSFB indicator to MME it initiates CSFB.

Comments

What about mobile Terminated (MT) calls?