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Catalyst 3750-X and 3560-X Switch Software Configuration Guide
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Chapter 13 Configuring Interface Characteristics Interface Types
10-Gigabit Ethernet Interfaces
The Catalyst 3750-X and 3560-X switches have a network module slot into which you can insert a
10-Gigabit Ethernet network module, a 1-Gigabit Ethernet network module, or a blank module.
A 10-Gigabit Ethernet interface operates only in full-duplex mode. The interface can be configured as a
switched or routed port.
For more information about the Cisco TwinGig Converter Module, see the switch hardware installation
guide and your transceiver module documentation.
Power over Ethernet Ports
A PoE-capable switch port automatically supplies power to one of these connected devices if the switch
senses that there is no power on the circuit:
• Cisco pre-standard powered device (such as a Cisco IP Phone or a Cisco Aironet Access Point)
• IEEE 802.3af-compliant powered device
• IEEE 802.3at-compliant powered device
A powered device can receive redundant power when it is connected to a PoE switch port and to an AC
power source. The device does not receive redundant power when it is only connected to the PoE port.
After the switch detects a powered device, the switch determines the device power requirements and then
grants or denies power to the device. The switch can also sense the real-time power consumption of the
device by monitoring and policing the power usage.
This section has this PoE information:
• Supported Protocols and Standards, page 13-7
• Powered-Device Detection and Initial Power Allocation, page 13-8
• Power Management Modes, page 13-9
• Power Monitoring and Power Policing, page 13-10

Supported Protocols and Standards

The switch uses these protocols and standards to support PoE:
• CDP with power consumption—The powered device notifies the switch of the amount of power it
is consuming. The switch does not reply to the power-consumption messages. The switch can only
supply power to or remove power from the PoE port.
• Cisco intelligent power management—The powered device and the switch negotiate through
power-negotiation CDP messages for an agreed-upon power-consumption level. The negotiation
allows a high-power Cisco powered device, which consumes more than 7 W, to operate at its highest
power mode. The powered device first boots up in low-power mode, consumes less than 7 W, and
negotiates to obtain enough power to operate in high-power mode. The device changes to
high-power mode only when it receives confirmation from the switch.
High-power devices can operate in low-power mode on switches that do not support
power-negotiation CDP.