Wimax standards and Security The Wimax

Association L₂


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Association L₂ (network-assisted association reporting) is indicated in Figure 7.1(10 and 11). The MSS may request to perform association with network- assisted association reporting by sending the MOB_SCN-REQ message, which includes the MSS-selected TBS, to the SBS with scanning type 0b011. Then the SBS, as shown in Figure 7.1 (12 through 14), should request the TBS and the nBS with network-assisted association by sending the MOB_SCN- RSP message. The SBS will then coordinate the association procedure with the requested nBSs over the backbone as shown in Figure 7.1(11 through 14). The SBS may aggregate all ranging-related information into a single associ- ation result report (MOB_ASC-REP) message, which is called the RNG-RSP information. Afterward, the MSS is required to only transmit the code division multiple access (CDMA) ranging code at TBS as shown in Figure 7.1(10 and 13). When receiving this message, the MSS updates its association database (PHY offsets and CIDs) and timers for TBS. We can get T_L2 , the service DT for L₂ scheme during the handover process by
^TL₂ ^{= T}MSS4SBS ^{+ T}SBS4TBS ^{+ T}ID ^{+ T}SYN ^(7.4)
Table 7.1 is the comparison between the procedures of L₀, L₁, L₂ and the predicted handover scheme (PHS). From the table it is obvious how simple the PHS is.
TABLE 7.1
Comparison of L₀, L₁, L₂, and PHS
Scheme Ranging MSS« SBS SBS«nBS SBS«TBS
L₀ Contention-based No No No L₁ Limited ranging « « No L₂ Fast ranging « No «
PHS Fast ranging ← No No

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