Chapter 30: Unified Electronic Surveillance
STANDARD Revision 1.0 C4® CMTS Release 8.3 User Guide
© 2016 ARRIS Enterprises LLC. All Rights Reserved. 876
electronic surveillance consistent with the requirements of CALEA. As defined by the specification, the functionality
covered by this feature applies only to packets transmitted utilizing the capabilities of the Call Management System,
including enhanced Quality of Service as authorized. Only such packet streams are defined as calls by CALEA; therefore,
these are the only packet streams subject to surveillance. Thus, only networks employing full PacketCable DQoS can
leverage PacketCable Electronic Surveillance functionality.
There are three types of surveillance requests:
Pen Register – this type of request records call identifying information for all calls originated by a subject. This is one
flavor of CALEA Call Data.
Trap and Trace – this type of request records call identifying information for all calls received by a subject. This is the
second flavor of CALEA Call Data.
Interception – this type of request allows Law Enforcement Agents (LEAs) to listen to conversations of a subject. This is
CALEA Call Content.
Ninety percent (90%) of all surveillance orders are of the first two types, and the request is generally made for both Pen
Register and Trap and Trace simultaneously.
A request for electronic surveillance is initiated at the Call Management Server (CMS). The role of the C4/c CMTS in an
electronic surveillance request includes the following steps:
1. Recognize the request that has been initiated by the CMS.
2. Duplicate event messages and send them to the specified Delivery Function (DF), if the surveillance request involves
CALEA Call Data.
3. Duplicate media stream content and send the duplicate stream to the Delivery Function, if the surveillance request
involves CALEA Call Content.
When a surveillance request has been associated with a subscriber on the CMS and the subject under surveillance is
involved in a call, an Electronic Surveillance object is sent to the C4/c CMTS within the Gate-Set message sent to the C4/c
CMTS from the CMS. This object contains all or some subset of the following, depending on what type of surveillance
request has been made:
A flag which indicates the type of surveillance requested
The IP address of the Delivery Function to which Call Data should be forwarded
The port of the Delivery Function to which Call Data should be forwarded
The IP Address of the Delivery Function to which Call Content should be forwarded
The port of the Delivery Function to which Call Content should be forwarded
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