Cisco ASR 5000 Series, Обзор продукта

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PDN Gateway Overview
▀ Features and Functionality - Base Software
▄ Cisco ASR 5000 Series Product Overview
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accounting server is responsible for authorizing network nodes (GGSNs) to grant access to the user, as well as
grant quotas for either time connected or volume used. It is up to the network node to track the quota use, and
when these use quotas run low, the network node sends a request to the pre-paid server for more quota.
If the user has not used up the purchased credit, the server grants quota and if no credit is available to the
subscriber the call will be disconnected. ECS and DCCA manage this functionality by providing the ability to
setup quotas for different services.
Pre-paid quota in ECS is implemented using DIAMETER Credit Control Application (DCCA). DCCA
supports the implementation of real-time credit control for a variety of services, such as networks access,
messaging services, and download services.
In addition to being a general solution for real-time cost and credit control, DCCA includes these features:
Real-time Rate Service Information - DCCA can verify when end subscribers' accounts are exhausted
or expired; or deny additional chargeable events.
Support for Multiple Services - DCCA supports the usage of multiple services within one subscriber
session. Multiple Service support includes; 1) ability to identify and process the service or group of
services that are subject to different cost structures 2) independent credit control of multiple services
in a single credit control sub-session.
Refer to the Diameter Credit Control Application section for more information.
Post-paid : In a post-paid environment, the subscribers pay after use of the service. A AAA server is responsible
for authorizing network nodes (GGSNs) to grant access to the user and a CDR system generates G-CDRs/eG-
CDRs/EDRs/UDRs or Comma Separated Values (CSVs) for billing information on pre-defined intervals of
volume or per time.
Important:
Support for the Enhanced Charging Service requires a service licenses. For more information on
ECS, refer to the Enhanced Charging Service Administration Guide .
Content Analysis Support
The Enhanced Charging Service is capable of performing content analysis on packets of many different protocols at
different layers of the OSI model.
The ECS content analyzers are able to inspect and maintain state across various protocols at all layers of the OSI stack.
ECS system supports, inspects, and analyzes the following protocols:
IP
TCP
UDP
DNS
FTP
TFTP
SMTP
POP3
HTTP
ICMP