Cisco ASR 5000 Series, Обзор продукта

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Content Filtering Support Overview
Content Filtering Server Group Support ▀
Cisco ASR 5000 Series Product Overview ▄
OL-22938-02
Content Filtering Server Group Support
ECS supports the streamlined ICAP interface to leverage Deep Packet Inspection to enable external application servers
to provide their services without performing DPI, and without being inserted in the data flow. For example, with an
external Active Content Filtering (ACF) platform.
A high-level view of the streamlined ICAP interface support for external ACF is shown in the following figure.
Figure 176. High-Level View of Streamlined ICAP Interface with External ACF
External Active
Content Filter Server
MN/SS
CSN/PDN/
Internet
System with
ECS/CF
The system with ECS is configured to support DPI and the system uses this capability for content charging as well.
If a subscriber initiates a WAP (WAP1.x or WAP2.0) or Web session, the subsequent GET/POST request is detected by
the DPI function. The URL of the GET/POST request is extracted and passed, along with subscriber identification
information and the subscriber request, in an ICAP message to the application server.
In the case of Category-based Content Filtering solution, the application server checks the URL on the basis of its
category and other classifications like type, access level and content category and decides if the request should be
authorized, blocked, or redirected by answering to the GET/POST with:
A 200 OK message if the request is accepted.
A 302 Redirect message in case of redirection. This redirect message includes the URL to which the subscriber
should be redirected.