sponds message ConnectionReconfigurationComplete. Xw-AP WT Release Request RRC ConnectionReconfiguration RRC ConnectionReconfigurationComplete Figure 11.8. WT Release procedure initiated by the eNB entity The WT Release procedure initiated by the access point is described in Figure 11.9. 1) The access point sends the message Xw-AP WT Release Required to the eNB entity to request the release of radio resources from the Wi-Fi access. 2) The eNB entity responds with the message Xw-AP WT Release Confirm. 3) If necessary, the eNB entity sends the message RRC ConnectionReconfiguration to the mobile indicating the release of the radio resources. 4) The mobile responds message ConnectionReconfigurationComplete Carrier Aggregation Xw-AP WT Release Required Xw-AP WT Release Confirm RRC ConnectionReconfiguration RRC ConnectionReconfigurationComplete Figure 11.9. WT Release procedure initiated by the access point The procedure for changing the access point is initiated by the eNB entity and used to transfer the mobile context from a source AP to a target AP. This procedure is performed using the WT Release and WT Addition procedures. 11.3.2. LWIP aggregation The procedure for establishing the LWIP and IPSec tunnels is described in Figure 11.10. 1) The eNB entity configures the mobile with the message RRC ConnectionReconfiguration to perform measurements on Wi-Fi access in order to start the LWIP and IPSec tunnels establishment. 2) The mobile applies the new configuration and responds with the message RRCConnectionReconfigurationComplete. 3) The mobile sends to the eNB entity the message RRC WLANMeasurements containing the measurements performed on the Wi-Fi access. 4) The eNB entity sends the message Xw-AP LWIP Addition Request to request the security gateway (SeGW) to allocate resources for IPSec tunnel establishment. 5) If the security gateway accepts the request, it responds with the message Xw-AP LWIP Addition Request Acknowledge. 6) The eNB entity sends the message RRC ConnectionReconfiguration to the mobile to establis