n in the queues, ARQ state machine, counters, timers, header compression information, etc. The above handover procedures are illustrated in Figure 4-15. The normal operation in the figure corresponds to the Active Mode. The cell reselection process shown in the figure is part of the Scanning Mode, and the network re-entry process corresponds to the Initialization and Access States. However, as mentioned earlier, some of the network re-entry steps may be skipped and the process may be further streamlined depending on the conditions that were discussed in the previous sections. Figure 4-16 shows the IEEE 802.16n mobile-initiated handover process. In IEEE 802.16m, the handover procedure may be initiated by either the MS or BS. In MS-initiated handover, the MS sends a handover initiation message to the serving BS. The BS responds to the handover initiation message by sending a handover command message to the MS. In BS-initiated handover, the BS sends a handover command message to the MS. In both cases, the handover command message includes one or more target base stations. If the handover command message includes only one target BS, the MS executes the handover procedures as directed by the BS. An MS may send a handover indication message to the serving BS before the expiration of Disconnect Timer (i.e., the time interval before cessation of downlink/uplink services to the MS by the serving BS once the handover process is initiated). The serving BS stops downlink traffic transmission and uplink allocations to the MS after expiration of the disconnect timer or after reception of a handover indication message. If the handover command message includes more than one target base station, the MS selects one of these targets and informs the BS of its selection by sending a handover indication message to the serving BS before the expiration of the disconnect timer. The network re-entry procedures with the target BS may be accelerated (i.e., fast network re-entry) if the MS information is available to the target BS as explain