Cisco ASR 5000 Series, Обзор продукта

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Session Control Manager Overview
Features and Functionality - Licensed Enhanced Feature Support ▀
Cisco ASR 5000 Series Product Overview ▄
OL-22938-02
Chassis configured to support Interchassis Session Recovery communicate using periodic Hello messages.
These messages are sent by each chassis to notify the peer of its current state. The Hello message contains
information about the chassis such as its configuration and priority. A dead interval is used to set a time limit
for a Hello message to be received from the chassis' peer. If the standby chassis does not receive a Hello
message from the active chassis within the dead interval, the standby chassis transitions to the active state. In
situations where the redundancy link goes out of service, a priority scheme is used to determine which chassis
processes the session. The following priority scheme is used:
router identifier
chassis priority
SPIO MAC address
Checkpoint Messages
Checkpoint messages are sent from the active chassis to the inactive chassis. Checkpoint messages are sent at
specific intervals and contain all the information needed to recreate the sessions on the standby chassis, if that
chassis were to become active. Once a session exceeds the checkpoint duration, checkpoint data is collected on
the session. The checkpoint parameter determines the amount of time a session must be active before it is
included in the checkpoint message.
Important:
For more information on interchassis session recovery support, refer to the Interchassis Session
Recovery chapter in the System Enhanced Feature Configuration Guide .
IPSec Support
Encrypted IPSec tunnels are terminated and decrypted so that traffic coming from untrusted networks are secured before
entering the secure operator network. This prevents eavesdropping, hijacking, and other intrusive behavior from
occurring.
IP Security (IPSec) is a suite of protocols that interact with one another to provide secure private communications across
IP networks. These protocols allow the system to establish and maintain secure tunnels with peer security gateways.
Important:
IPSec implementation is a mandatory part of IPv6, but it is optional to secure IPv4 traffic.
Important:
For more information on IPSec support, refer to the IP Security chapter in the System Enhanced
Feature Configuration Guide .
IPv4-IPv6 Interworking
This feature allows the P-CSCF to provide IPv4-IPv6 interworking in the following scenarios:
When UEs are IPv6-only and the IMS core network is IPv4-only