Power Outage; Power Reduction; Power Negotiation Over Lldp - Cisco 8800 Series Manual

Technical Details
Table 91: Additional Information
Document topics
PoE Solutions
UPoE
Cisco Catalyst Switches
Integrated Service Routers
Cisco IOS Software

Power Outage

Your access to emergency service through the phone requires that the phone receive power. If a power
interruption occurs, service or emergency calling service dialing does not function until power is restored. If
a power failure or disruption occurs, you may need to reset or reconfigure the equipment before you can use
service or emergency calling service dialing.

Power Reduction

You can reduce the amount of energy that the Cisco IP Phone consumes by using Power Save mode.
Power Save

Power Negotiation Over LLDP

The phone and the switch negotiate the power that the phone consumes. Cisco IP Phone operates at multiple
power settings, which lowers power consumption when less power is available.
After a phone reboots, the switch locks to one protocol (CDP or LLDP) for power negotiation. The switch
locks to the first protocol (containing a power Threshold Limit Value [TLV]) that the phone transmits. If the
system administrator disables that protocol on the phone, the phone cannot power up any accessories because
the switch does not respond to power requests in the other protocol.
Cisco recommends that Power Negotiation always be enabled (default) when connecting to a switch that
supports power negotiation.
If Power Negotiation is disabled, the switch may disconnect power to the phone. If the switch does not support
power negotiation, disable the Power Negotiation feature before you power up accessories over PoE. When
In Power Save mode, the backlight on the screen is not lit when the phone is not in use. The phone
remains in Power Save mode until the user lifts the handset or presses any button. Set up each phone to
enable or disable Power Save settings.
Cisco IP Phone 8800 Series Multiplatform Phone Administration Guide for Release 11.3(1) and Later
URL
http://www.cisco.com/c/en/us/solutions/
enterprise-networks/power-over-ethernet-solutions/
index.html
http://www.cisco.com/c/en/us/solutions/
enterprise-networks/upoe/index.html
http://www.cisco.com/c/en/us/products/switches/
index.html
http://www.cisco.com/c/en/us/products/routers/
index.html
http://www.cisco.com/c/en/us/products/
ios-nx-os-software/index.html
Power Outage
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