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Cisco uBR10012 Universal Broadband Router Software Configuration Guide
OL-1520-05
Chapter4 Managing Cable Modems on the Hybrid Fiber-Coaxial Network Activating CM Insertion Interval
Examples The following example shows how to activate CM authentication using 3344912349988...sf as the
shared secret key and indicating that an encrypted message follows:
Router(config-if)# cable shared-secret 7 3344912349988cisco@xapowenaspasdpuy230jhm...sf

Verify CM Authentication

To verify whether CM authentication is activated or deactivated, enter the command more
system:running-config and look for the cable interface configuration information. If CM authentication
is deactivated, it appears in this output as no cable secret-shared.
Activating CM Insertion Interval
When a CM is ready to transmit data, it requests a channel from the CiscouBR10012router. You can
limit the amount of time that a CM requests a channel for the first time from the CiscouBR10012router.
A CM's initial channel request is known as insertion. The valid range is 100 to 2000 milliseconds.
To activate the CM insertion interval, use the following command in cable interface configuration mode.

Validating CM Insertion Interval

To verify that a CM insertion interval has been set, enter the command moresystem:running-config
command, and look for the cable interface configuration information, as shown in this command output
excerpt:
Router# more system:running-config
Building configuration...
Current configuration:
!
interface Cable5/0/0
ip address 1.1.1.1 255.255.255.0
no keepalive
cable insertion-interval 2000
cable downstream annex B
cable downstream modulation 64qam
cable downstream interleave-depth 32
cable downstream symbol-rate 5056941
cable upstream 0 frequency 15008000
cable upstream 0 fec
cable upstream 0 scrambler
no cable upstream 0 shutdown
!

Troubleshooting CM Insertion Interval

If you are having trouble, make sure that you entered the correct slot and port numbers when you typed
the command.
Command Purpose
cable insertion-interval milliseconds Sets the insertion interval in milliseconds.