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Cisco IE 2000 Switch Software Configuration Guide
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Chapter 15 Configuring Interface Characteristics
Information About Configuring Interface Characteristics
Routed Ports
Note The LAN base image supports static routing.
A routed port is a physical port that acts like a port on a router; it does not have to be connected to a
router. A routed port is not associated with a particular VLAN, as is an access port. A routed port behaves
like a regular router interface, except that it does not support VLAN subinterface s. Routed ports can be
configured with a Layer 3 routing protocol. A routed port is a Layer 3 interface only and does not supp ort
Layer 2 protocols, such as DTP and STP. Routed ports are supported only on switches running the IP
base or IP services image.
Configure routed ports by putting the interface into Layer 3 mode with the no switchport interface
configuration command. Then assign an IP address to the port, ena ble routing, and assign routing
protocol characteristics by using the ip routing and router protocol global configuration commands.
Note Entering a no switchport interface configuration command shuts down the interface and then reenables
it, which might generate messages on the device to which the interface is connected. When you put an
interface that is in Layer 2 mode into Layer 3 mode, the previous configuration information related to
the affected interface might be lost.
The number of routed ports that you can configure is not limited by software. However, the
interrelationship between this number and the number of other f eatures being configured might impact
CPU performance because of hardware limitations.
For more information about IP unicast routing and routing prot ocols, see Chapter 41, “Configuring IP
Unicast Routing”
Access Ports
An access port belongs to and carries the traffic of only one VLAN (unless it is configured as a voice
VLAN port). Traffic is received and sent in native formats with no VLAN tagging. Traffic arriving on
an access port is assumed to belong to the VLAN assigned to the port.
If an access port receives an 802.1Q tagged packet, the packet is droppe d, and the source address is not
learned.
Two types of access ports are supported:
• Static access ports are manually assigned to a VLAN (or through a RADIUS server for use with
IEEE 802.1x. For more information, see the “802.1x Authentication with VLAN Assignment”
section on page 13-15.
• VLAN membership of dynamic access ports is learned through incoming packets. By default, a
dynamic access port is not a member of any VLAN, and forwarding to and from the port is enabled
only when the VLAN membership of the port is discovered. Dynamic access ports on the switch are
assigned to a VLAN by a VLAN Membership Policy Server (VMPS). The VMPS can be a
Catalyst 6500 series switch; the switch cannot be a VMPS server.
You can also configure an access port with an attached Cisco IP Phone to use one VLAN for voice traffic
and another VLAN for data traffic from a device attached to the phone. For more information about voice
VLAN ports, see Chapter 19, “Configuring Voice VLAN.”