
Information About Control Point Discovery
To configure the Control Point Discovery feature, you should understand the following concepts:
Control Points
Control points are points in a network that can be used to apply certain functions and controls for a media
stream. In a cable environment, the control points are Cable Modem Termination Systems (CMTS) and devices
that utilizes these control points are referred to as CPD Requestors (or controllers).
Cable CPD Requestors include the following:
•
Call Management Server (CMS)
•
Policy Server (PS)
•
Mediation Device for Lawful Intercept (MD)
Network Layer Signaling (NLS)
Network Layer Signaling (NSL) is an on-path request protocol used to carry topology discovery and other
requests in support of various applications. In the CPD feature, NLS is used to transport CPD messages.
NLS for CPD
NLS is used to transport CPD messages. The CPD data is carried under an application payload of the NLS
and contains a NLS header with flow id. The NLS flow id is used during NLS authentication to uniquely
identify the CPD requests and responses for an end point of interest.
NLS Flags
All NLS headers contain bitwise flags. The CMTS expects the following NLS flag settings for CPD applications:
•
HOP-BY-HOP = 0
•
BUILD-ROUTE = 0
•
TEARDOWN = 0
•
BIDIRECTOINAL = 0
•
AX_CHALLANGE = 0/1
•
AX_RESPONSE = 0/1
Any requests with flags other then AX flags, set to one will be rejected with an error indicating a poorly
formed message.
Note
Cisco cBR Series Converged Broadband Routers Troubleshooting and Network Management Configuration Guide
for Cisco IOS XE Fuji 16.8.x
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Control Point Discovery
Information About Control Point Discovery