Installation guide

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Cisco uBR7100 Series Universal Broadband Router Software Configuration Guide
OL-2238-03
Chapter 3 Configuring the Cisco Cable Interface
Activating Cable Address Resolution Protocol Requests
Assigning the Spectrum Group and the Upstream Ports
After determining which upstream ports you want assigned to a combiner group, perform the following
steps to configure a frequency hop table.
Verifying Spectrum Group and Upstream Port Assignments
Use the show cable spectrum-group command to display the current allocation table and frequency
assignments.
Activating Cable Address Resolution Protocol Requests
Address Resolution Protocol (ARP) is an Internet protocol used to map IP addresses to MAC addresses
on computers and other equipment installed in a network. You need to activate ARP requests on the cable
interface so that the Cisco uBR7100 series CMTS can perform IP address resolution on the downstream
path.
Note The default values for the commands used in this configuration step are adequate in most cases to
configure the Cisco uBR7100 series CMTS.
Activating Cable Address Resolution Protocol (ARP) Requests
To activate ARP requests, use the following command in cable interface configuration mode:
Verifying ARP Requests
To verify if cable ARP is activated, enter the more system:running-config and look for the cable
interface configuration information. If ARP is activated, it does not appear in this output. If ARP is
deactivated, it appears in the output as
no cable arp.
CMTS01# more system:running-config
Building configuration...
Command Purpose
Step 1
CMTS01(config)# interface cable slot/port
Enter cable interface configuration mode for the interface
to which you wish to assign a spectrum group.
Step 2
CMTS01(config-if)# cable spectrum-group usport
Assign the spectrum group to the interface.
Step 3
CMTS01(config-if)# cable upstream number
spectrum-group usport
Assign the upstream ports to the spectrum group for the
interface.
Step 4
CMTS01(config-if)# no cable upstream slot/port
shutdown
Place the upstream port in the “admin up” state.
Step 5
CMTS01(config-if)# exit
CMTS01# test cable hop c1/0
CMTS01# test cable hop c1/0
Exit configuration mode and force the system to hop.
Command Purpose
CMTS01(config-if)# cable arp
Enable ARP. This is the default.