LTE X2 handover sequence diagram

The sequence diagrams below cover the LTE X2 handover between eNodeBs served by the same MME. To inspect an X2 handover in a live trace, VisualEther turns a Wireshark capture into the same kind of sequence diagram — RRC, X2AP, and the data-path switch included.

LTE X2 handover sequence diagram

eNodeBs in LTE are interconnected with the X2 interface. If two eNodeBs are served by the same MME, handover from the source to the target eNodeB will take place over the X2 interface.

X2 handover overview

Get an overview of the interactions between a UE, eNodeBs and the Core Network

UE interactions

Focus on UE interactions in a X2 handover

Source eNodeB

Source eNodeB role in an X2 interface handover

Target eNodeB

Target eNodeB interactions in an X2 handover

RRC signaling

RRC signaling interactions in an X2 handover

X2AP signaling

X2AP signaling in an X2 handover

Data flow

Data flow during an X2 handover