•
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 increases 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 switch
information at this URL:
http://cisco.com/en/US/products/hw/switches/index.html
Related Topics
Phone Startup Process, on page 25
Configuration Menus, on page 35
Cisco Unified IP Phone Power
The Cisco Unified SIP Phone 3905 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.
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.
Note
Power Guidelines
The following table provides guidelines for powering the Cisco Unified SIP Phone 3905.
Table 4: Guidelines for Powering the Cisco Unified SIP Phone 3905
Guidelines
Power Type
The Cisco Unified SIP Phone 3905 uses the Cisco Unified SIP Phone 3905
Power Adapter.
External power: Provided
through the Cisco Unified
SIP Phone 3905 Power
Adapter.
The Cisco Unified IP Phone Power Injector may be used with any Cisco Unified
IP Phone. Functioning as a midspan device, the injector delivers inline power
to the attached phone. The Cisco Unified IP Phone Power Injector is connected
between a switch port and the IP Phone, and supports a maximum cable length
of 100m between the unpowered switch and the IP Phone.
External power: Provided
through the Cisco Unified
IP Phone Power Injector.
Cisco Unified SIP Phone 3905 Administration Guide for Cisco Unified Communications Manager 8.6 (SIP)
23
Cisco Unified IP Phone and Your Network
Cisco Unified IP Phone Power