Cisco Systems uBR7200 Series Activate Cable Modem Authentication, Verify Sync Message Interval

Chapter 4 Troubleshooting the System

Managing Cable Modems on the HFC Network

Verify Sync Message Interval

To verify whether or not a sync message interval is configured, enter the show running-configcommand and look for the cable interface configuration information. If the sync message interval is deactivated or reset to its default value, the no sync interval command line appears in the output.

Activate Cable Modem Authentication

The Cisco uBR7200 series can be configured to require all cable modems to return a known text string to register with the CMTS and gain access to the network. The text string can be from 1 to 80 characters in length. To activate cable modem authentication, use the following command from cable interface configuration mode.

Table 4-2	Instructions to Activate Cable Modem Authentication
Command		Purpose
CMTS01(config-if)#cable shared-secret [07]		Enable cable modem authentication: 0 specifies an
authorization-key		unencrypted authentication key; 7 specifies an
		encrypted authentication key.

CMTS01(config-if)#no cable shared-secret

Disable cable modem authentication.

Tips Be sure you enter the correct slot and port number in the cable interface configuration mode. Verify that the cable modem is using BPI and that it is assigned to a QoS with privacy active. Verify that the cable modem configuration file contains a matching key.

Verify Cable Modem Authentication

To verify whether cable modem authentication is activated or deactivated, enter the command more system:running-configand look for the cable interface configuration information. If cable modem authentication is deactivated, it appears in this output as no cable secret-shared.

Activate Cable Modem Upstream Address Verification

Cable modem upstream address verification ensures that only cable modems that have received DHCP leases through the Cisco uBR7200 series can access the HFC network. The Cisco uBR7200 series discards all packets received from or for hosts that have not received DHCP-assigned addresses.

Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide

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