Cisco ASR 5000 Series, Обзор продукта

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GGSN Support in GPRS/UMTS Wireless Data Services
▀ How GGSN Works
▄ Cisco ASR 5000 Series Product Overview
OL-22938-02
12.
The FA forwards the registration request from the MS to the HA while the MS‘s home address or NAI and TEID
are stored by the GGSN.
13. The HA sends a registration response to the FA containing the address assigned to the MS.
14.
The FA extracts the home address assigned to the MS by the HA from the response and the GGSN updates the
associated PDP context. The FA then forwards it to the MS (identified by either the home address or the NAI
and TEID).
15.
The GGSN issues a PDP context modification procedure to the SGSN in order to update the PDP address for the
MS.
16.
The SGSN forwards the PDP context modification message to the MS.
The MS can now send and receive data to or from their home network until the session is closed or times out.
Note that for Mobile IP, only one PDP context is supported for the MS.
17.
The MS can terminate the Mobile IP data session at any time. To terminate the Mobile IP session, the MS sends
a Registration Request message to the GGSN/FA with a requested lifetime of 0.
18.
The FA component forwards the request to the HA.
19.
The HA sends a Registration Reply to the FA accepting the request.
20. The GGSN/FA forwards the response to the MN.
21.
The MS sends a Deactivate PDP Context Request message that is received by the SGSN.
22.
The SGSN sends a Delete PDP Context Request message to the GGSN facilitating the data session. The message
includes the information elements necessary to identify the PDP context.
23.
The GGSN removes the PDP context from memory and returns a Delete PDP Context Response message to the
SGSN.
24.
The SGSN returns a Deactivate PDP Context Accept message to the MS.
25.
The GGSN delivers the GGSN Charging Detail Records (G-CDRs) to a Charging Gateway (CG) using GTP
Prime (GTPP). Note that, though not shown in this example, the GGSN could optionally be configured to send
partial CDRs while the PDP context is active.
26.
For each accounting message received from the GGSN, the CG responds with an acknowledgement.
Proxy Mobile IP Call Flows
The following figure and the text that follows describe a sample successful Proxy Mobile IP session setup call flow in
which the MS receives its IP address from the HA.