Handover is initiated by ENB on receiving MEASUREMENT_REPORT from the UE’s. The handover decision is also taken by the ENB and not the EPC. The handover also involves the exchange of various packets. 

1. First UE sends MeasurementReport packets to the ENB. 
2. ENB takes the Handover decision and sends the HandoverRequest packet to the target ENB. 
3. In response, the Target ENB sends the HandoverRequestAck packet back to the source ENB. 
4. This completes the process of Handover.
5. After this LTE Association happens between the target ENB and the UE that was handed over.                                                    

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