Cisco ASR 5000 Series, Обзор продукта

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Peer-to-Peer Overview
How P2P Works ▀
Cisco ASR 5000 Series Product Overview ▄
OL-22938-02
How P2P Works
P2P interfaces to a PCRF Diameter Gx interface to accept policy ACLs and rulebases from a PDF. P2P supports real-
time dynamic policy updates during a subscriber session. This includes modifying the subscriber‘s policy rules during
an active session by means of ACL name and Rulebase name.
In Rel. 7 Gx interface, a Charging Rulebase will be treated as a group of ruledefs. A group of ruledefs enables grouping
rules into categories, so that charging systems can base the charging policy on the category. When a request contains
names of several Charging Rulebases, groups of ruledefs of the corresponding names are activated. For P2P rules to
work in the group of ruledefs, P2P detection has to be enabled in the rulebase statically.
Static policy is supported initially. A default subscriber profile is assumed and can be overwritten on the gateway. Per-
subscriber static policy is pulled by the gateway from the AAA service at subscriber authentication.
The following figure illustrates how packets travel through the system using P2P detection. The packets are investigated
and then handled appropriately using ruledefs for charging.
Figure 212. Overview of Packet Processing in ECSv2
P2P Detection
Protocol
Analyzer Stack
ruledefs
(rule-application charging)
Charging Engine
block
Xmit
redirect
string, =, >, !, etc.
Call
detail
records
Incoming
packets
Packet
inspection
output
Advantages of P2P Processing Before DPI