Cisco 7246VXR - uBR Router - DOCSIS and CMTS Interoperability; DOCSIS NTSC Cable Plants

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Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide
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Chapter 1 Overview of Cisco uBR7200 Series Software
DOCSIS and CMTS Interoperability
DOCSIS and CMTS Interoperability
This section contains the following topics to familiarize you with DOCSIS architectural fundamentals:
• “DOCSIS NTSC Cable Plants” section on page 1-137
• “EuroDOCSIS Cable Plants” section on page 1-138
• “DOCSIS-Compliant Downstream Signals” section on page 1-139
• “DOCSIS-Compliant Upstream Signals” section on page 1-140
• “Traffic Engineering” section on page 1-142
DOCSIS NTSC Cable Plants
DOCSIS-compliant cable plants that support North American channel plans use ITU J.83 Annex B RF.
Figure 1-1 illustrates a DOCSIS two-way and telco-return architecture.
Figure 1-1 DOCSIS Two-Way and Telco-Return Architecture
PSTN
Telco return
access
Distribution hub or headend
Operation
support system
Cable modem
termination system
(CMTS)
Mod
Demod
Downstream
RF interface
Upstream
RF interface
Video 1
Video 2
Data
Data
Upstream
splitter
and filter
bank
Controller
50-860 MHz
NTSC
5-42MHz
NTSC
Coax
Fiber
Tx
Distribution
network
Node
RF
interface
Telco
return
Cable modem
telco return
interface
34972
Cable
modem
Rx
Network
termination
Security &
access
controller
Port
Adapter
Local
server
facility
WAN
WAN
Remote
server
facility
Backbone
network
Node
Node
Data over
cable service
specification
(DOCSIS)