e interval should be long enough SO that the network re-entry procedure with the target BS can be completed prior to the expiration of this timer. When using an AAI_HO-CMD message with multiple target BSs and carriers, the physical index of each candidate carrier is provided 11.4 MAC aspects of multi-carrier operation (Serving) Fully- Fully- Fully- Fully- Fully- Fully- Configured Configured Configured Configured Configured Configured Carrier 1 Carrier 2 Carrier 1 Carrier 2 Carrier 1 Carrier 2 AAI_NBR-ADV (N_Neighbors=2) (Multi-carrier Configuration) AAI_SCN-REQ (Scan Duration = N Frames, Interleaving Interval =P Frames, Iteration = T Times) AAI_SCN-RSP (start Frame = M Frames) (duration = N Frames) M Frames Synchronize With Carrier 2 Of BS 1 Synchronize With Carrier 1 Of BS 2 Synchronize With Carrier 2 Of BS 2 Synchronize With Carrier 1 Of BS 3 Synchronize With Carrier 2 Of BS 3 Non-scanning Data Transmission Interleaving Interval (P Frames) Additional Alternations of Scanning Interval and Interleaving Intervals FIGURE 11-11 Neighbor-BS advertisement and scanning procedure [2] by each target BS, and is included in the AAI_HO-CMD message. The candidate base stations identified in the AAI_HO-CMD message can instruct the MS to make a decision on handover, if the CINR/RSSI measurement on one of the base stations is sufficiently good to meet the QoS requirements of the MS. The MS may inform the serving BS of the component carrier that it is going use for network re-entry in order to avoid resource allocation on that carrier during the process. Once network entry is completed, the MS stops communication with the serving BS and may transmit data (if the user-plane is already established) or a bandwidth request message to the target BS. The serving and target base station may negotiate secondary carrier pre-assignment as illustrated in Figure 11-14. If the Carrier_Preassignment_Indication parameter is set to 1 in the AAI_HO-CMD message, the pre-assignment information is forwarded by the target base stations to the servin