Cisco ASR 5000 Series, Обзор продукта

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Enhanced Charging Service Overview
▀ Introduction
▄ Cisco ASR 5000 Series Product Overview
OL-22938-02
Introduction
The ECS is an in-line service that is integrated within the system. ECS enhances the mobile carrier‘s ability to provide
flexible, differentiated, and detailed billing to subscribers with Layer 3 through Layer 7 packet inspection, and the
ability to integrate with back-end billing system.
Charging Subsystem
The ECS has analyzers that examine uplink and downlink traffic and rules that define what packet content to take action
on and what action to take when the rule is true. The analyzers also generate usage records for the billing system.
The various functions of ECS subsystem are:
Traffic analysis
Content insertion
Credit control/quota reservation for prepaid services
Redirection
Advice of charge and user notifications
Usage data generation
QoS optimization
Traffic Analyzers
Traffic analyzers in ECS are based on configured rules. Rules used for traffic analysis analyze packet flows and form
usage records. Usage records are created per content type and forwarded to a prepaid server or to a billing system.
The Traffic Analyzer function can perform shallow (Layer 3 and Layer 4) and deep (above Layer 4) packet inspection
of IP packet flows. It is able to correlate all layer 3 packets (and bytes) with higher layer trigger criteria (for example,
URL detected in an HTTP header). It also performs stateful packet inspection for complex protocols like FTP, RTSP,
and SIP that dynamically open ports for the data path and this way, user plane payload is differentiated into
―categories‖. Traffic analyzers can also detect video streaming over RTSP, and image downloads and MMS over HTTP
and differential treatment can be given to the Vcast traffic.
Traffic analyzers work at the application level as well, and perform event-based charging without the interference of the
service platforms.
The ECS content analyzers can inspect and maintain state across various protocols at all layers of the OSI stack. The
ECS supports inspecting and analyzing the following protocols:
Domain Name System (DNS)