Cisco Cisco IOS Software Release 12.1(3)EC
Cisco uBR7200 Series Dynamic Upstream Modulation
Configuration Examples
8
Cisco IOS Release 12.1(3a)EC1
Verifying Your Settings
Step 1
Enter the show running-config command at the Router# prompt to check the value of the settings you
have entered.
have entered.
Router# show running-config
To review changes you make to the configuration, use the show startup-config command to display the
information stored in NVRAM.
information stored in NVRAM.
Step 2
Use the show cable modulation-profile privileged EXEC command to display modulation profile
group information.
group information.
Router# show cable modulation-profile [profile] [iuc-code]
profile—(Optional) Profile number. Valid values are from 1 to 8.
iuc-code—(Optional) Internal usage code.
Valid options are:
–
initial—initial ranging burst
–
long— long grant burst
–
request—request burst
–
short—short grant burst
–
station— station ranging burst
Configuration Examples
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Modulation Profiles Example
The Cisco uBR7200 series Cisco IOS Release 12.1(3a)EC1 has one preconfigured modulation profile
resident in memory, which defines a typical profile for QPSK modulation. In order to use the
Dynamic Upstream Modulation feature, a second profile must be created that is unique from the first
profile, and typically provides a higher modulation scheme.
resident in memory, which defines a typical profile for QPSK modulation. In order to use the
Dynamic Upstream Modulation feature, a second profile must be created that is unique from the first
profile, and typically provides a higher modulation scheme.
The following example is a modulation profile for 16QAM, in which the initial, request, and station
maintenance messages are sent as QPSK, and the short and long data packets are sent as 16QAM.
16QAM modulation is more bandwidth-efficient than QPSK, but QPSK is more robust than 16QAM.
maintenance messages are sent as QPSK, and the short and long data packets are sent as 16QAM.
16QAM modulation is more bandwidth-efficient than QPSK, but QPSK is more robust than 16QAM.