License Requirements; Supported Standards; How It Works - Cisco ASR 5000 Administration Manual

Gx Interface Support

License Requirements

The Rel. 6 Gx interface support is a licensed Cisco feature. A separate feature license may be required. Contact your
Cisco account representative for detailed information on specific licensing requirements. For information on installing
and verifying licenses, refer to the Managing License Keys section of the Software Management Operations chapter in
the System Administration Guide.

Supported Standards

The Rel 6. Gx interface support is based on the following standards and request for comments (RFCs):
 3GPP TS 29.210, Charging rule provisioning over Gx interface
 RFC 3588, Diameter Base Protocol; September 2003
 RFC 4006, Diameter Credit-Control Application; August 2005
In addition to the above RFCs and standards, IMS Authorization partially supports 3GPP TS 29.212 for Policy and
Charging Control over Gx reference point functionality.

How it Works

This section describes the IMS authorization and dynamic policy support in GPRS/UMTS networks.
The following figure and table explain the IMS authorization process between a system and IMS components that is
initiated by the MN.
In the case of GGSN, the DPCA is the Gx interface to the Control and Charging Rule Function (CRF). In this context
CRF will act as Enhanced Policy Decision Function (E-PDF). The CRF may reside in Proxy-Call Session Control
Function (P-CSCF) or on stand-alone system.
The interface between IMSA with CRF is the Gx interface, and between Session Manager and Online Charging Service
(OCS) is the Gy interface.
Note that the IMS Authorization (IMSA) service and Diameter Policy Control Application (DPCA) are part of Session
Manager on the system, and separated in the following figure for illustration purpose only.
OL-27210-02
Important:
Note that Charging rule provisioning over Gx interface functionality is not
supported in 14.0 and later releases.
Cisco ASR 5000 IP Services Gateway Administration Guide ▄
Rel. 6 Gx Interface ▀
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