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Configuring ISG Integration with SCE
Prerequisites for Configuring ISG Integration with SCE
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Prerequisites for Configuring ISG Integration with SCE
The following prerequisites apply to the configuration of ISG integration with SCE.
Hardware Requirements
•
An ISG platform, which can be a Cisco ASR 1000 series router
• An SCE platform
•
Two connections between the ISG device and the SCE:
– A control path, through which the ISG device and SCE can exchange policy information
–
A data path that carries the subscriber traffic
• A policy server configured to communicate with the ISG platform. The ISG-SCE integration
removes any need for a communication layer between the policy server and the SCE.
Restrictions for Configuring ISG Integration with SCE
The following restrictions apply to the integration of the ISG and an SCE:
•
When an SCE policy is deactivated, the policy is removed from the session on the SCE, and the
session policy reverts to the default SCE policy.
• Only one SCE policy at a time may be applied to a session. Applying additional policies will
override the policy previously applied on the SCE.
This feature requires a control bus communication protocol, which runs over RADIUS and RADIUS
extensions (as specified in RFC 3576), operating in two modes; PUSH and PULL.
• In PULL mode the ISG device waits for a query from the SCE.
•
In PUSH mode the download of an external feature is initiated by the ISG device as soon as an
external service is activated on the subscriber session.
To work with the SCE for subscriber management, the control bus protocol must do the following:
•
Support pushing a session and make relevant changes to a session to the SCE.
• Allow a session, its relevant identity, and the SCE policy profile to be pulled from the ISG device
by using an identity-based query.
•
Support accounting events, including the following:
– Accepting SCE initiated accounting events asynchronously.
–
Correlating SCE accounting data to the appropriate ISG session.
– Parsing the SCE accounting data to perform protocol translation.
Information About Configuring ISG Integration with SCE
Before you configure ISG integration with SCE, you should understand the following concepts:
•
Overview of ISG-SCE Integration, page 3
• ISG and SCE Roles in Subscriber Management, page 3