Cisco ASR 5000 Series, Обзор продукта

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PDN Gateway Overview
▀ Features and Functionality - Base Software
▄ Cisco ASR 5000 Series Product Overview
OL-22938-02
Registration Revocation is a general mechanism whereby either the P-GW or the HSGW providing Mobile IP
functionality to the same mobile node can notify the other mobility agent of the termination of a binding. Mobile IP
Registration Revocation can be triggered at the HSGW by any of the following:
Session terminated with mobile node for whatever reason
Session renegotiation
Administrative clearing of calls
Session Manager software task outage resulting in the loss of HSGW sessions (sessions that could not be
recovered)
Important:
Registration Revocation functionality is also supported for Proxy Mobile IP. However, only the P-
GW can initiate the revocation for Proxy-MIP calls.
Important:
For more information on MIP registration revocation support, refer to the Mobile IP Registration
Revocation chapter in the System Enhanced Feature Configuration Guide .
Session Recovery Support
Provides seamless failover and reconstruction of subscriber session information in the event of a hardware or software
fault within the system preventing a fully connected user session from being disconnected.
In the telecommunications industry, over 90 percent of all equipment failures are software-related. With robust
hardware failover and redundancy protection, any card-level hardware failures on the system can quickly be corrected.
However, software failures can occur for numerous reasons, many times without prior indication. StarOS Release 9.0
adds the ability to support stateful intra-chassis session recovery for P-GW sessions.
When session recovery occurs, the system reconstructs the following subscriber information:
Data and control state information required to maintain correct call behavior
Subscriber data statistics that are 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
Session recovery is also useful for in-service software patch upgrade activities. If session recovery is enabled during the
software patch upgrade, it helps to preserve existing sessions on the active PSC/PSC2 during the upgrade process.
Important:
For more information on session recovery support, refer to the Session Recovery chapter in the
System Enhanced Feature Configuration Guide .