ations for the MS at each target BS for optimized network re-entry. The handover command includes an action time for the MS to start network re-entry with each target BS, and an indication whether the MS should continue communication with the serving BS during network re- entry. The handover command further contains a disconnect timer, which indicates when the serving BS will stop sending downlink data and other regularly scheduled unsolicited uplink allocations for the MS. In the case where the MS can maintain communication with the serving BS during network re- entry, the transmission parameters for concurrent communication with both serving and target base stations are determined by the serving BS, depending on the MS capability that is negotiated between the serving and target base stations. The handover command indicates if the MS static and/or dynamic context is available at the target BS. If the HO_Re-entry_Mode field of the handover command is set to 1, the serving BS will negotiate with the target BS the Entry Before Break (EBB) handover parameters (see Figure 6-16). In the case of single-carrier handover, the EBB HO parameters include HO_Re-entry_Interleaving_Interval and HO_Re-entry_Iteration for the MS to communicate with the serving BS during network re-entry. In the CHAPTER 6 The IEEE 802.1 16m MAC CPS (Part I) Seamless HO Enabled? CDMA-based CDMA-based Ranging Enabled? Ranging Enabled? Use Dedicated Ranging Code/ Use Dedicated Dedicated Ranging Opportunity Ranging Code/ Code/Opportunity Opportunity AAI_RNG-ACK Randomly Select HO AAI_RNG-ACK Ranging Code Continue Success Success Data Communication with Target BS and AAI_RNG-REQ/RSP AAI_RNG-REQ/RSP HO Complete FIGURE 6-16 Mobile station behavior during handover network re-entry [2] multicarrier handover case, the EBB HO parameters include the carrier information in the target BS for the MS performing network re-entry while continuing to communicate with the serving BS. Handover Execution The MS performs network re-entry with the target BS within the 