Cisco Cisco Packet Data Interworking Function (PDIF) Guía Para Resolver Problemas
IP Pool Sharing Protocol
▀ How IPSP Works
▄ Cisco ASR 5000 Series Enhanced Feature Configuration Guide
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IPSP Operation for Session Handoffs
The following figure and text describe how session handoffs are handled when IPSP is enabled.
Figure 19. IPSP Operation for Session Handoffs
MN
AAA
1
2
3
4
7
5
8
9
HA2
HA1
Table 13. IPSP Operation for Session Handoffs Description
Step
Description
1
A mobile node (MN) is connected to PDSN/FA 1.
2
The MN‘s session is handed-off to PDSN/FA2 and goes through the re-registration process.
3
PDSN/FA 2 authenticates the subscriber with the AAA server as part of the re-registration process. One of the attributes
returned by the AAA server as part of a successful authentication is the IP address of the secondary HA.
returned by the AAA server as part of a successful authentication is the IP address of the secondary HA.
4
PDSN/FA 2 forwards the session request to HA2 for processing. Included in the request is the MN‘s current IP address.
5
With IPSP enabled, prior to assigning an IP address, HA2 sends a request to HA1 for an IP address.
6
HA1 verifies the MN‘s information and releases the binding. It then busies out the address so it can not be re-assigned.