PDN Gateway Overview
▀ Features and Functionality - Base Software
▄ Cisco ASR 5x00 Packet Data Network Gateway Administration Guide
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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
WAP: WTP and WSP
Real-Time Streaming: RTP and RTSP
MMS
SIP and SDP
File analysis: examination of downloaded file characteristics (e.g. file size, chunks transferred, etc.) from file
transfer protocols such as HTTP and FTP.
Traffic analyzers in enhanced charging subsystem 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 pre-paid server or
to a mediation/billing system. A traffic analyzer performs shallow (Layer 3 and Layer 4) and deep (above Layer 4)
packet inspection of the IP packet flows.
The Traffic Analyzer function is able to do a 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 (e.g. URL detected in a HTTP
header) and it is also perform stateful packet inspection to complex protocols like FTP, RTSP, SIP that dynamically
open ports for the data path and by this way, user plane payload is differentiated into “categories”.
The Traffic Analyzer works on the application level as well and performs event based charging without the interference
of the service platforms.
Important:
This functionality is available for use with the Enhanced Charging Service which requires a session-
use license. For more information on ECS, refer to the
Enhanced Charging Service Administration Guide
.
Content Service Steering
Content Service Steering (CSS) directs selective subscriber traffic into the ECS subsystem (In-line services internal to
the system) based on the content of the data presented by mobile subscribers.
