eived over S1 in case of inter-eNodeB handover or successful handover indication delivered inside the eNodeB to source cell in case of intra-eNodeB handover divided by the number of sent RRC connection reconfiguration messages by source eNodeB (caused by received handover request acknowledgement over X2 or received handover command over S1). It should be noted that in this chapter only the intra-LTE, intra-frequency handover performance is discussed. In Chapter 15, inter-frequency and inter-radio access technology handover performance are considered. The handover execution procedure for inter-eNodeB scenario is shown in Figure 12.25. Having as optimal as possible neighbour plan per each cell with optimized handover param- eters is the main factor for high handover execution success rate. Therefore, the automatic neighbour relations (ANR) and mobility robustness optimization (MRO) algorithms should be utilized in order to optimize the neighbour plan, handover triggering parameters and UE mobility performance in general. These algorithms are discussed in Section 12.6 and in this section the handover signalling and resource allocation for messages are analysed. During the resource allocation phase the target eNodeB allocates the following parameters which are given to the source eNodeB within the X2AP Handover Request Acknowledge LTE Key Performance Indicator Optimization message and to the UE by the source eNodeB within the RRC Connection Reconfiguration message: The target cell physical cell identity (PCI). T304 supervises the handover procedure from the UE point of view: started when the UE receives RRC Connection Reconfiguration message containing mobility control information and stopped once the UE has successfully completed the random access procedure and sent the RRC Connection Reconfiguration Complete message to the target cell (eNodeB). New C-RNTI, which is used by the UE right after the random access procedure for PDCCH DCI monitoring under the target cell. In case of contention-free random access procedur