Cisco 7800 Series Administration Manual page 21

Table 4: Guidelines for Cisco IP Phone Power
Power Type
External power: Provided
through the
CP-PWR-CUBE-3=
external power supply
External power—Provided
through the Cisco IP Phone
Power Injector.
PoE power—Provided by a
switch through the Ethernet
cable attached to the phone.
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.
Supported Network Protocols
Cisco IP Phones support several industry-standard and Cisco network protocols that are required for voice
communication. The following table provides an overview of the network protocols that the phones support.
Table 5: Supported Network Protocols on the Cisco IP Phone
Network Protocol
Bootstrap Protocol (BootP)
Guidelines
The Cisco IP Phone uses the CP-PWR-CUBE-3 power supply.
The Cisco IP Phone Power Injector may be used with most Cisco IP Phones.
The phone datasheet identifies if the phone can use the power injector.
Functioning as a midspan device, the injector delivers inline power to the
attached phone. The Cisco IP Phone Power Injector connects between a switch
port and the IP Phone, and supports a maximum cable length of 100m between
the unpowered switch and the IP phone.
To ensure uninterruptible operation of the phone, make sure that the switch
has a backup power supply.
Make sure that the CatOS or IOS version that runs on your switch supports
your intended phone deployment. See the documentation for your switch for
operating system version information.
Purpose
BootP enables a network device, such as
the Cisco IP Phone, to discover certain
startup information, such as its IP address.
Cisco IP Phone 7800 Series for Third-Party Call Control Administration Guide
Supported Network Protocols
Usage Notes
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