Key Guidelines for
Implementing IP
Routing
Configure Trunks
(Optional)
Your module, as a routing device, has the ability to implement either type
of routing scheme, "routing over bridging" and "routing versus
bridging". Each kind of routing scheme requires its own interface type:
Routing over Bridging requires a VLAN-based IP Interface — A
VLAN-based interface requires you to first configure a VLAN and then
create a router interface over that VLAN.
Routing versus Bridging requires a Port-based IP Interface — A
port-based interface requires you to configure a router interface on
top of a single physical port.
To route network traffic using IP, you must perform these tasks in the
following order:
1 Configure Trunks (Optional)
2 Configure IP VLANs
3 Establish Your IP Interfaces
4 Enable IP Routing
Trunks (also known as aggregated links) work at Layer 2 and allow you to
combine multiple Fast Ethernet or Gigabit Ethernet into a single
high-speed link between two switches.
If you intend to use trunking on an IP device, configure your trunks
before you set up VLANs and IP interfaces. In this case, you must specify
the anchor port (the lowest-numbered port) to associate with the trunk.
For example, if ports 7 through 12 are associated with a trunk, specifying
7 to 12 defines the VLAN to include all of the physical ports in the trunk
(ports 7 through 12).
For more information about trunking, see Chapter 12.
Key Guidelines for Implementing IP Routing
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