Cisco ASR 5000 series Product Overview page 739

Enhanced Charging Service Overview
Figure 180. Routing Ruledefs and Packet Inspection
Incoming
packets
1
Step 1
The packet is redirected to ECS based on the ACLs in the subscriber's template /APN and packets enter ECS through
the Protocol Analyzer Stack.
Step 2
Packets entering Protocol Analyzer Stack first go through a shallow inspection by passing through the following
analyzers in the listed order:
Step a
Step b
Step c
Important:
Therefore, defining routing ruledefs for these analyzers is not required.
Step 3
The fields and states found in the shallow inspection are compared to the fields and states defined in the routing ruledefs
in the subscriber's rulebase.
The ruledefs' priority determines the order in which the ruledefs are compared against packets.
Step 4
When the protocol fields and states found during the shallow inspection match those defined in a routing ruledef, the
packet is routed to the appropriate layer 7or 7+ analyzer for deep-packet inspection.
Step 5 After the packet has been inspected and analyzed by the Protocol Analyzer Stack:
Step a
Step b
Applied actions include redirection, charge value, and billing record emission.
OL-22938-02
Protocol
Analyzer Stack
Bearer IP
Anlayzer Analyzer
TCP ICMP UDP
Analyzer Analyzer Analyzer
2
Shallow Inspection
Bearer Analyzer
IP Analyzer
ICMP, TCP, or UDP Analyzer as appropriate
In the current release traffic routes to the ICMP, TCP, and UDP analyzers by default.
The packet resumes normal flow and through the rest of the ECS subsystem.
The output of that analysis flows into the Charging Engine, where an action can be applied.
5a
3
Routing
Ruledefs
5b
Other
Analyzers
4
Deep
Inspection
Outgoing
packets
data flows,
states, and
statistics
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