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
This feature provides support for up to 800 AAA server groups and 800 NAS IP addresses that can be provisioned
within a single context or across the entire chassis. A total of 128 servers can be assigned to an individual server group.
Up to 1,600 accounting, authentication and/or mediation servers are supported per chassis.
Important:
Due to additional memory requirements, this service can only be used with 8GB Packet Service
Cards (PSCs).
Dynamic Policy Charging Control (Gx Reference Interface)
Dynamic policy and charging control provides a primary building block toward the realization of IMS multimedia
applications. In contrast to statically provisioned architectures, the dynamic policy framework provides a centralized
service control layer with global awareness of all access-side network elements. The centralized policy decision
elements simplify the process of provisioning global policies to multiple access gateways. Dynamic policy is especially
useful in an Always-On deployment model as the usage paradigm transitions from a short lived to a lengthier online
session in which the volume of data consumed can be extensive. Under these conditions dynamic policy management
enables dynamic just in-time resource allocation to more efficiently protect the capacity and resources of the network.
Dynamic Policy Control represents the ability to dynamically authorize and control services and application flows
between a Policy Charging Enforcement Function (PCEF) on the P-GW and the PCRF. Policy control enables a
centralized and decoupled service control architecture to regulate the way in which services are provisioned and
allocated at the bearer resource layer.
The StarOS 9.0 release includes enhancements to conform with 3GPP TS 29.212 and 29.230 Release 8 functions. The
Gx reference interface uses Diameter transport and IPv6 addressing. The subscriber is identified to the PCRF at session
establishment using IMSI based NAI's within the Subscription-ID AVP. Additionally the IMEI within the Equipment-
Info AVP is used to identify the subscriber access terminal to the policy server. The Gx reference interface supports the
following capabilities:
Authorize the bearer establishment for a packet flow
Dynamic L3/L4 transfer of service data flow filters within PCC rules for selection and policy enforcement of
downlink/uplink IP CAN bearers
Support static pre-provisioned L7 rulebase name attribute as trigger for activating Inline Services such as Peer-
to-Peer Detection
Authorize the modification of a service data flow
Revoke the authorization of a packet flow
Provision PCC rules for service data flows mapped to default or dedicated EPS bearers
Support P-GW initiated event triggers based on change of access network gateway or IP CAN
Provide the ability to set or modify APN-AMBR for a default EPS bearer
Create or modify QoS service priority by including QCI values in PCC rules transmitted from PCRF to PCEF
functions