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Cisco uBR10012 Universal Broadband Router Software Configuration Guide
OL-1520-05
Chapter 3 Configuring Cable Interface Features for the Cisco uBR10012 Router
Configuring Optional Cable Interface Features
The bandwidth request drop count (from the previous nonshaping test) remains unchanged when
upstream rate shaping is used, indicating that the CMTS is actually shaping (buffering) the grants for the
modem. Verify that the input rate at the CMTS (from the single rate-exceeded CM) stabilizes close to
the configured peak rate of 128 Kbps.
Troubleshooting Tips
Perform these steps if you are having difficulty with verification:
Step 1
Ensure that the cable connections are not loose or disconnected.
Step 2
Ensure that the cable interface line card is firmly seated in its chassis slot.
Step 3
Ensure that the captive installation screws are tight.
Step 4
Verify that you have entered the correct slot and port numbers.
Step 5
Verify that you selected a valid frequency for your router.
Configuring Optional Cable Interface Features
This section builds on the required cable interface features documented earlier in this chapter. This
section provides instructions for several optional cable interface configurations. These interface features
pertain to heightened performance and security measures.
Note
Default settings are typically adequate to configure optional features on the system. Change default
settings only with careful prior analysis.
Activating Host-to-Host Communication (Proxy ARP)
Cable proxy ARP allows the Cisco uBR10012 router to issue cable ARP requests on behalf of CMs on
the same cable network subnet.
Section
Purpose
“Activating Host-to-Host
Communication (Proxy ARP)” section
on page 3-26
Allows the Cisco uBR10012 router to issue cable Address
Resolution Protocol (ARP) requests on behalf of CMs on the
same cable network subnet.
“Activating Packet Intercept
Capabilities” section on page 3-28
Specifies a MAC address on the cable network for which
interception capabilities are to be activated.
“Configuring Payload Header
Suppression and Restoration” section
on page 3-28
Provides command information to set up the Payload Header
Suppression (PHS) feature, which is used to suppress
repetitive or redundant portions in packet headers before
transmission on the DOCSIS link.
“Setting Optional Broadcast and Cable
IP Multicast Echo” section on
page 3-29
Sets additional IP parameters to enable downstream echoing
of upstream data.