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Cisco Unified IP Phone 7975G Administration Guide for Cisco Unified Communications Manager 7.0 (SCCP and SIP)
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Chapter 2 Preparing to Install the Cisco Unified IP Phone on Your Network
Providing Power to the Phone
You can resolve these issues by isolating the voice traffic onto a separate VLAN. The switch port that
the phone is connected to would be configured to have separate VLANs for carrying:
•
Voice traffic to and from the IP phone (auxiliary VLAN, on the Cisco Catalyst 6000 series, for
example)
•
Data traffic to and from the PC connected to the switch through the access port of the IP phone
(native VLAN)
Isolating the phones on a separate, auxiliary VLAN improves the quality of the voice traffic and allows
a large number of phones to be added to an existing network where there are not enough IP addresses
for each phone.
For more information, refer to the documentation included with a Cisco switch. You can also access
related documentation at this URL:
http://cisco.com/en/US/products/hw/switches/index.html
Related Topics
•
Understanding the Phone Startup Process, page 2-7
•
Network Configuration Menu, page 4-5
Providing Power to the Phone
The Cisco Unified IP Phone 7975G can be powered with external power or with Power over Ethernet
(PoE). External power is provided through a separate power supply. PoE is provided by a switch through
the Ethernet cable attached to a phone.
Note
When you install a phone that is powered with external power, connect the power supply to the phone
and to a power outlet before you connect the Ethernet cable to the phone. When you remove a phone that
is powered with external power, disconnect the Ethernet cable from the phone before you disconnect the
power supply.
The following sections provide more information about powering a phone:
•
Power Guidelines, page 2-4
•
Phone Power Consumption and Display Brightness, page 2-4
•
Power Outage, page 2-5
•
Obtaining Additional Information about Power, page 2-5