Creating Network-Layer Bridges - ADC CUDA 3 Administration Manual

Creating Network-Layer Bridges

Cuda 12000 IP Access Switch CLI-based Administration Guide
The key to spanning a single subnet across multiple DOCSIS modules is to
configure the same IP gateway on each module. Because the gateway serves
as the key that dictates address assignment for cable modems, CPE devices
or MTAs, configuring the same IP gateway on each cable interface enables
the DHCP server to assign those devices IP addresses from the same subnet
or subnet pool.
For example, this means that cable modems attached to a DOCSIS module in
slot 1 can belong to the same subnet as the modems attached to a DOCSIS
module in slot 8. You can then physically move modems between DOCSIS
module without assigning new addresses; the shift of modems between
modules becomes plug and play.
To span a subnet across multiple cable interfaces, perform the following
steps:
1. Create a bridge group, as described in "Creating Bridge Groups" on
page 347.
2. Add the cable interfaces on which you want to install the same gateway
to the bridge group, as described in "Adding Interfaces to Bridge
Groups" on page 349.
3. Assign the IP address that you want to use as the cable modem, CPE, and
MTA gateway to the bridge group, as described in "Assigning IP
Addresses To Bridge Groups" on page 351. Note that the address that
you assign to the bridge group is automatically added to the routing
table.
4. Configure the DHCP relay agent on each cable interface so that the IP
address is configured as the cable modem, CPE, and/or MTA gateway.
Creating Network-Layer Bridges 345