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Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide
OL-2239-05
Chapter 1 Overview of Cisco uBR7200 Series Software
Supported Software Features for the Cisco uBR7200 Series
cable upstream
n
scheduling type
Use this new command to turn the various scheduling modes on or off, where
n
specifies the upstream port.
Router(config-if)# [
no
]
cable upstream
n
scheduling type
[
ugs
|
rtps
]
mode
[
llq
|
docsis
]
For additional information about scheduler enhancements on the Cisco CMTS, refer to the following
documents on Cisco.com:
•
Cisco CMTS Feature Guide — Configuring Upstream Scheduler Modes on the Cisco CMTS
http://www.cisco.com/en/US/docs/cable/cmts/feature/guide/ufg_schd.html
•
DOCSIS 1.1 for the Cisco CMTS
http://www.cisco.com/en/US/docs/cable/cmts/feature/guide/ufg_docs.html
DOCSIS 2.0 Feature Support
This section describes DOCSIS 2.0 enhancements supported on the Cisco uBR7200 series:
•
DOCSIS 2.0 A-TDMA Support, page 1-67
DOCSIS 2.0 A-TDMA Support
Support for DOCSIS 2.0 A-TDMA on the Cisco uBR7200 series commences with Cisco IOS Release
12.2(15)CX and continues with later releases in the 12.2 CX, 12.2 BC and 12.3 BC release trains.
The Cisco uBR-MC16U/X and Cisco uBR-MC28U/X cards improve the maximum upstream bandwidth
on existing DOCSIS 1.0 and DOCSIS 1.1 cable networks by providing a number of advanced PHY
capabilities that have been specified by the new DOCSIS 2.0 specifications.
The DOCSIS 2.0 A-TDMA Support feature incorporates the following advantages and improvements of
DOCSIS 2.0 networks:
•
Builds on existing DOCSIS cable networks by providing full compatibility with existing DOCSIS
1.0 and DOCSIS 1.1 cable modems. (The registration response (REG-RSP) message contains the
DOCSIS version number to identify each cable modem's capabilities.)
•
Upstreams can be configured for three different modes to support different mixes of cable modems:
–
An upstream can be configured for TDMA mode to support only DOCSIS 1.0 and DOCSIS 1.1
cable modems.
–
An upstream can be configured for A-TDMA mode to support only DOCSIS 2.0 cable modems.
–
An upstream can be configured for a mixed, TDMA/A-TDMA mode, to support both DOCSIS
1.0/DOCSIS 1.1 and DOCSIS 2.0 cable modems on the same upstream.
Note
DOCSIS 2.0 A-TDMA cable modems will not register on a TDMA upstream if an A-TDMA or
mixed upstream exists in the same MAC domain, unless the CMTS explicitly switches the cable
modem to another upstream using an Upstream Channel Change (UCC) message. DOCSIS 1.0
and DOCSIS 1.1 cable modems cannot register on an A-TDMA only upstream.
•
A-TDMA mode defines new interval usage codes (IUC) of A-TDMA short data grants, long data
grants, and Unsolicited Grant Service (UGS) grants (IUC 9, 10, and 11) to supplement the existing
DOCSIS 1.1 IUC types
•
Increases the maximum channel capacity for A-TDMA upstreams to 30 Mbps per 6 MHz channel.
•
A-TDMA and mixed modes of operation provide higher bandwidth on the upstream using new
32-QAM and 64-QAM modulation profiles. In addition, an 8-QAM modulation profile is supported.