CHAPTER
3-1
CiscouBR924 Software Configuration Guide
OL-0337-05 (8/2002)
3
Advanced Data-Only Configurations
This chapter describes how to configure the Cisco uBR924 cable acc ess router for data operation with
features beyond those supported in the default operation mode of “plug and play” DOCSIS bridging. Th e
following configurations are described:
•Data-Only Routing, page 3-2
•Routing with DHCP Server, page 3-4
•NAT/PAT Configuration, page 3-6
•NAT/PAT Configuration with DHCP Proxy, page 3-8
•IPSec (56-bit) Example, page 3-11
•IPSec (3DES) Example, page 3-16
•L2TP Example, page 3-17
Depending on the Cisco IOS software image being used and the f eature sets it supports, these
configurations could be combined.
Tip Use the commands shown in this chapter to set up a typical CiscouBR924 router for the desired feature.
Then save the configuration into a configuration file that can be downloaded to the router during
power-on or reset.
Caution Incorrectly configuring the Cisco uBR924 cable access router can cause loss of network connectivity.
Before attempting to reconfigure the router, print the last working configuration, and ensure remote
configuration is enabled for the site.
If the router does not connect to the network after you have reconfigured it, enter the cable downstream
saved frequency from the printout, and then clear the interface. Power off and then power on the router.
If powering off the router does not correct the problem after a f ew minutes, give the write erase and
copy startup-config running-config commands; then enter the correct saved downstream frequency. If
network connectivity is not restored, contact your network management, provisioning, or b illing system
administrator to reload the software applicable to your network.