 while the UE tries to complete the random access procedure 5. The UE acquired system re-establishment message and timer with the target cell. In case the UE can information of the target cell. The T301 is stopped. SRB1 is resumed successfully complete the random access UE layer 3 sends RRC connection and layer 3 sends RRC connection procedure the T304 timer is stopped and re-establishment message to the re-establishment complete message RRC connection reconfiguration lower layers. T311 is stopped and to physical layer and procedure T301 started complete message sent to the target cell Figure 12.29 RRC connection re-establishment caused by T304 expiry LTE Small Cell Optimization 1. Random access procedure triggered due no response to the 3. Random access problem indication, 6. The UE acquires UL grant via SRI on PUCCH (the UE sends the if T300, T301, T304 or T311 is not random access procedure and SRI on PRACH) or eNB sends running the UE detects radio link physical layer sends RRC connection PDCCH order (to initiate PRACH failure and starts T311 re-establishment request message procedure for, e.g. reacquiring UL synchronization) 4. The UE finds suitable cell Random access procedure T311 running 7. The UE receives RRC connection 2. Random access procedure is 5. The UE acquired system re-establishment message and timer attempted until maximum number of information of the target cell. The T301 is stopped. SRB1 is resumed preambles transmitted UE layer 3 sends RRC connection and layer 3 sends RRC connection re-establishment message to the re-establishment complete message lower layers. T311 is stopped and to physical layer and procedure T301 started Figure 12.30 RRC connection re-establishment caused by non-handover-triggered random access procedure failure Non-handover-Related Random Access Failure The UE initiates non-handover-related random access procedure due to receiving PDCCH order (containing contention-free preamble identifier), for example, for re-establishment of uplink synchronization (lost due to the lo