as a handover target. The MS may use neighbor advertisement messages from the serving BS or may negotiate scanning intervals with the BS to search and select candidate base stations for handover. The cell reselection is performed in the Scanning Mode and as part of the Connected State. 4.2.1 Normal Network Re-Entry As shown in Figure 4-1, normal network re-entry is performed when an MS in the Idle State transitions to the Connected State (through Access State) as a result of paging or availability of scheduled uplink data or messages for transmission. The Initialization State procedures may be skipped, depending on whether system information at the MS is up-to-date and downlink synchronization with the cell has been maintained during idle period. Also during handover, the MS must perform a successful network re-entry with the target BS to establish data-plane and start or resume data transmission with the new BS. During network re-entry, the MS sends a ranging request message that includes a Ranging Purpose Indication parameter and Paging Controller ID. If the target BS has not already received the MS information over the backhaul, then the target BS may request the information from the paging controller over the core network. Regardless of having received the MS information from the paging controller, the target BS may request the MS information from another network management entity via the backhaul. The network re-entry is similar to network entry, except it may be shortened by the target BS's possession of MS information obtained from paging controller or other network entity over the backbone. In order to notify an MS seeking network re-entry from Idle State about the procedural steps that may be omitted during its network re-entry attempt (due to the availability of the MS service and operational context), the target BS includes a handover process optimization parameter in the ranging response message to the MS, indicating which re-entry management messages may be skipped [1]. Furthermore, if the target BS 