Which parameter used by eNB to decide X2 handover depending on Event A2 measurement?

Question

In case of hub-and-spoke topology, X2 messaging can travel all the way back to an aggregation point, which may be co-located with EPC. In such scenario both X2 and S1 traverses same physical path (a.k.a X2 over S1). Please consider both Intra-MME and Inter-MME handover scenarios. Would X2 based handover in such a case yield advantage over S1 based handover. Thanks.

Answer 1

X2 handover can be triggered only if x2 interface is available between source eNB and target eNB. There is no relation of A2 with X2. X2 interface just make handover faster as compared to s1 handover. Event A2 is triggered when serving cell becomes worse than configured threshold. RSRP or RSRQ is being for threshold. eNodeB also configured number of report need to be sent from UE to eNodeB.

Please check 36.331 for more details.