What is the difference between X2ho with AM mode and UM mode bearer? Tell me scenario for each one?

Question

Is any restriction on number of bearer of AM/UM rlc mode per UE?

Answer 1

For the AM mode bearers, source eNodeB sends SN status transfer message to target eNodeB for the E-RABs that have PDCP SN and HFN preservation. For the UM mode no need to transfer PDCP SN and HFN to target eNodeB. That is the main difference what I know for X2 handover having AM mode bearers and without having AM mode bearers.