Understanding How The Cisco Unified Ip Video Phone Interacts With The Cisco Catalyst Family Of Switches - Cisco 7985G - IP Phone NTSC Video Administration Manual

Chapter 2 Preparing to Install the Cisco Unified IP Video Phone on Your Network
Understanding How the Cisco Unified IP Video Phone Interacts
with the Cisco Catalyst Family of Switches
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Understanding Interactions with Other Cisco Unified IP Telephony Products
Related Topic
Telephony Features that are Available for the Phone, page 5-2
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The Cisco Unified IP Video Phone 7985G includes an internal Ethernet switch
that enables proper forwarding of appropriate packets to the phone, to the access
port (labeled 10/100 PC on the phone), and to the network port (labeled
10/100 SW on the phone).
If a computer is connected to the PC port, the computer and the phone share the
same physical link to the switch and share the same port on the switch. The
following implications for the VLAN configuration on the network apply for the
shared physical link:
The current VLANs configuration may be on an IP subnet basis; however,
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additional IP addresses may not be available to assign the phone to the same
subnet as other devices that connect to the same port.
Data traffic that exists on the VLAN-supported phones may reduce the
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quality of voice-over-IP traffic.
You can resolve these issues by isolating the voice and video traffic onto a
separate VLAN on each port that is connected to a phone. The switch port that is
configured for the phone connection would have separate VLANs that are
configured for carrying:
Voice and video traffic to and from the IP phone (auxiliary or voice VLAN)
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Data traffic to and from the PC connected to the switch through the PC port
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of the IP phone (native or access 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 enough IP addresses for each phone do not exist.
For more information, refer to the documentation that is included with the
Cisco Catalyst switch.
Related Topics
Understanding Phone Configuration Files, page 2-6
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Cisco Unified IP Video Phone 7985G Administration Guide
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