Downstream Frequency Override - Cisco 7246VXR - uBR Router Software Configuration Manual

Chapter 1 Overview of Cisco uBR7200 Series Software
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DOCSIS 1.1 Two-way Transmission (Cisco uBR7246VXR Router)
The Cisco uBR7200 series routers allow DOCSIS 1.1 two-way transmission of digital data and Voice
over IP (VoIP) traffic over a hybrid fiber-coaxial (HFC) network. The Cisco uBR7200 series support IP
routing with a wide variety of protocols and combinations of Ethernet, Fast Ethernet, Gigabit Ethernet,
serial, High-Speed Serial Interface (HSSI), Packet over SONET (POS) OC-3 and OC-12c, and
Asynchronous Transfer Mode (ATM) media.
Downstream Channel ID
This feature allows all cable modems in an HFC network to identify themselves via unique downstream
channel IDs instead of their downstream frequencies.
To configure the downstream channel ID, use the cable downstream channel-id configuration
command. Use the no form of this command to set the downstream channel ID to its default value.
id
Syntax DescriptionS
For additional information, refer to the following documents on Cisco.com:
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Downstream Frequency Override

Downstream frequency override allows the CMTS administrator to change the downstream frequency
assigned to a cable modem, overriding the frequency set in the cable modem DOCSIS configuration file.
To enable cable downstream frequency override, use the cable downstream override command in cable
interface configuration mode. To disable the override feature, use the no form of this command.
For additional command information, refer to the following document on Cisco.com:
OL-2239-05
Best effort-Data traffic sent on a non-guaranteed best-effort basis
Committed Information Rate (CIR)—Guaranteed minimum bandwidth for data traffic
Unsolicited Grants (UGS)—Constant bit rate (CBR) traffic, such as voice, that is characterized by
fixed size packets at fixed intervals
Real Time Polling (rtPS)—Real Time service flows, such as video, that produce unicast, variable
size packets at fixed intervals
Unsolicited Grants with Activity Detection (USG-AD)—Combination of UGS and RTPS, to
accommodate real time traffic that might have periods of inactivity (such as voice using silence
suppression). The service flow uses UGS fixed grants while active, but switches to RTPS polling
during periods of inactivity to avoid wasting unused bandwidth.
Enhanced time-slot scheduling mechanisms to support guaranteed delay/jitter sensitive traffic on the
shared multiple access upstream link
cable downstream channel-id id
no cable downstream channel-id
Specifies a downstream channel ID. Valid values are from 1 to 255.
Configuring Downstream Channel IDs
http://www.cisco.com/en/US/docs/ios/12_0t/12_0t4/feature/guide/downchan.html
Cisco IOS CMTS Cable Command Reference Guide
http://www.cisco.com/en/US/docs/ios/cable/command/reference/cbl_book.html
cable downstream override
no cable downstream override
Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide
Supported Software Features for the Cisco uBR7200 Series
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