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Catalyst 4500 Series, Catalyst 2948G, Catalyst 2948G-GE-TX, and Catalyst 2980G Switches Software Configuration Guide
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Release 8.2GLX
78-15908-01
Chapter 29 Configuring VoIP
Overview of IP Phones
Overview of IP Phones
Catalyst 4000 series and 4500 series can connect to a Cisco IP Phone and carry IP voice traffic. If
necessary, the switch can supply electrical power to the circuit connecting it to a Cisco IP Phone.
Cisco classifies three types of IP phones based on the discovery methods that are used to discover the
phone:
•
Legacy Cisco IP Phone—Uses a Cisco proprietary discovery method to detect an IP phone and uses
“link disconnect” to verify that an IP phone has been removed from the network
•
Cisco/IEEE 802.3af compliant—Uses enhanced Cisco Discovery Protocol (CDP) and /or IEEE
802.3af to discover and remove an IP phone
•
Third-party IEEE 802.3af compliant—Uses IEEE 802.3af specified “detection of phone” to detect
an IP phone and “detection of phone removed” to verify that an IP phone has been removed from
the network.
An IP phone contains an integrated three-port 10/100 switch. The ports are dedicated connections as
described below:
•
Port 1 connects to the switch or other device that supports VoIP.
•
Port 2 is an internal 10/100 interface that carries the phone traffic.
•
Port 3 connects to a PC or other device.
Figure 29-1
shows one way to configure an IP Phone.
Figure 29-1 IP Phone Connected to a Catalyst 4500 Series Switch
When you connect an IP phone to a 10/100 port on the Catalyst 4500 series switch, you can use the
access port (PC-to-phone jack) of the IP phone to connect a PC.
Packets to and from the PC and to and from the phone share the same physical link to the switch and the
same port of the switch.
Table 29-1 Catalyst 4500 Series Components Supporting Inline Power
Switch Chassis
Modules
Power Supplies
Catalyst 4006
WS-X4148-RJ45V
1
1.
The Catalyst 4006 switch can provide only a maximum 400 W of inline power per module.
Catalyst 4000 Family Power Entry
Module (PEM)
Catalyst 4503
Catalyst 4506
WS-X4148-RJ45V
1300 W AC
2800 W AC
1400 W DC
IP Phone
Catalyst 4500 Family Switch
PC
99519
IP