Cisco ASR 5000 Series, Обзор продукта

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ASN Paging Controller and Location Registry Overview
Introduction ▀
Cisco ASR 5000 Series Product Overview ▄
OL-22938-02
Step Description
4 If the anchor PC retains context information for the MS including its Authenticator ID, the anchor PC initiates a Context
Request procedure with the anchor authenticator/ASN Gateway. If the anchor authenticator/ASN Gateway has valid key
material for the MS, it returns AK context for the MS to the Anchor PC.
5 Upon successful retrieval of the AK context, the anchor PC sends an R4 LU_Rsp message back to the serving ASN
Gateway and starts timer TR4_LU_Conf. The message includes the MSID, BSID, Authenticator ID, assigned PGID,
Paging Offset, Paging Cycle, Anchor PC ID TLVs, and Location Update Status TLV set to Accept. Upon receipt of the R4
LU_Rsp message, the serving ASN Gateway stops timer TR4_LU_Req.
6 Upon receipt of the R4 LU_Rsp message, the serving ASN Gateway stops timer TR4_LU_Req, sends an R6 LU_Rsp
message to the serving ASN BS, and starts timer TR6_LU_Conf. The message includes the Location Update Status TLV
set to Accept, AK Context TLVs, as well as the assigned Paging Information TLV if they were included in the
corresponding R4 message.
7 Based on the AK and AK context received from the anchor PC, the serving BS (associated with Local PC/Relay PC in
serving ASN Gateway) successfully authenticates the RNG_REQ message received from the MS and sends a RNG_RSP
message with HMAC/CMAC and Successful LU_Rsp indication to the MS.
8 The serving ASN BS initiates an R6 CMAC Key Count Update procedure with the ASN Gateway. The serving ASN
Gateway initiates an R4 CMAC Key Count Update procedure with the authenticator ASN to update it with the latest
CMAC Key Count.
9 The serving ASN BS sends an R6 LU_Cnf message to the serving ASN Gateway with Location Update TLV indicating
success. Upon receipt of the message, the serving ASN Gateway stops timer TR6_LU_Conf.
10 The serving ASN Gateway sends an R4 LU_Cnf message with a successful LU indication to the anchor PC and stops timer
TR6_LU_Req. Upon receipt of the message, the anchor PC updates the LR with MS Idle Mode information and stops timer
TR4_LU_Conf.
Location Update with Paging Controller Relocation
This section describes the secure location update with PC relocation procedure for a WiMAX MS.
The following figure and table provides a high-level view of the steps involved in a secure location update with PC
relocation.
Table 48. Location Update with PC Relocation - Procedure Flow
Step Description
1 The MS initiates a secure Location Update procedure by sending a RNG-REQ message to the serving ASN BS, which
includes the Ranging Purpose Indication TLV set to indicate Idle Mode Location Update, the PC ID TLV which points to
the anchor ASN Gateway acting as the anchor PC function for the MS, and the HMAC/CMAC tuple.
2 The serving BS sends an R6 LU_Req message to the serving ASN Gateway and starts timer TR6_LU_Req. The message
may include the PG ID, Paging Offset, and Paging Cycle TLVs if the serving BS proposes an update to these parameters.
3 The serving ASN Gateway (associated with the serving BS and local PC) sends an R4 LU_Req message to the anchor PC
ASN associated and starts timer TR4_LU_Req. The message may include the PG ID, Paging Offset, and Paging Cycle
TLVs if the serving ASN proposes an update to these parameters. Note that this message may be relayed by several
intermittent ASNs before reaching the current anchor PC ASN. The serving ASN or any intermittent ASN along the path
may request PC relocation.