Cisco Systems UBR900 User Manual

 Configuring the Cisco uBR900 Series Cable Access Routers 63

To enable the QPSK modulation scheme in the upstream direction from the cable access router 
interface to the headend, enter the cable-modem upstream preamble qpsk command from 
interface configuration mode. Use the no form of this command to disable upstream modulation for 
the interface.

Syntax Description

This command has no arguments or keywords.

Defaults

Enabled

Command Modes

Interface configuration

Command History

Usage Guidelines

Examples

The following example shows how to enter the cable-modem upstream preamble qpsk command 
for a cable access router interface, starting from global configuration mode:

uBR924(config)# interface cable-modem 0

uBR924(config-if)# cable-modem upstream preamble qpsk

uBR924(config-if)# 

11.3 NA

This command was  introduced.