Question: In a Handover Cancel procedure initiated by the source eNB in an E-UTRAN, what action does the target eNB take upon receiving the HANDOVER CANCEL message regarding resources and UE context?
Option 1: The target eNB updates the UE context with new resource allocations and keeps all previously reserved resources.
Option 2: The target eNB removes any reference to and releases any resources previously reserved for the concerned UE context.
Option 3: The target eNB puts the UE context in a dormant state without releasing or allocating new resources.
Option 4: The target eNB ignores the HANDOVER CANCEL message if the New eNB UE X2AP ID IE is not included.
Explanation: According to E-UTRAN handover cancellation procedures, upon receiving a HANDOVER CANCEL message, the target eNB must release resources and remove references that were set aside for the UE's handover. This ensures efficient resource management and prevents unnecessary allocations. Option 2 correctly reflects this procedure, highlighting the importance of resource cleanup in failed or cancelled handovers to maintain network efficiency.