Asr 5500 System Administration Guide, Staros Release 21.4 - Cisco ASR 5000 Series Administration Manual

Session Recovery
• ASR 5500 only – HNB-GW: HNB-CN Session over IuPS and IuCS
• ASR 5500 only – HNB-GW: SeGW Session IPSec Tunnel
• ASR 5500 only – HSGW services for IPv4
• IPCF (Intelligent Policy Control Function)
• ASR 5500 only – IPSG-only systems (IP Services Gateway)
• LNS session types (L2TP Network Server)
• MME (Mobility Management Entity)
• ASR 5500 only – NEMO (Network Mobility )
• P-GW services for IPv4
• ASR 5500 only – PDIF (Packet Data Interworking Function)
• PDSN services supporting simple IP, Mobile IP, and Proxy Mobile IP
• S-GW (Serving Gateway)
• SaMOG (S2a Mobility over GTP) Gateway (CGW and MRME)
• ASR 5500 only – SAE-GW (System Architecture Evolution Gateway)
• ASR 5500 only – SGSN services (3G and 2.5G services) for IPv4 and PPP PDP contexts
Session recovery is not supported for the following functions:
• Destination-based accounting recovery
• GGSN network initiated connections
• GGSN session using more than 1 service instance
• MIP/L2TP with IPSec integration
• MIP session with multiple concurrent bindings
• Mobile IP sessions with L2TP
• Multiple MIP sessions
Always refer to the Administration Guides for individual products for other possible session recovery and
Important
Interchassis Session Recovery (ICSR) support limitations.
When session recovery occurs, the system reconstructs the following subscriber information:
• Data and control state information required to maintain correct call behavior.
• A minimal set of subscriber data statistics; required to ensure that accounting information is maintained.
• A best-effort attempt to recover various timer values such as call duration, absolute time, and others.
• The idle time timer is reset to zero and the re-registration timer is reset to its maximum value for HA
sessions to provide a more conservative approach to session recovery.

ASR 5500 System Administration Guide, StarOS Release 21.4

How Session Recovery Works
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