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Cisco Unified IP Phone Administration Guide for Cisco Unified CallManager 5.0 (SCCP), Cisco Unified IP Phones
OL-8151-01
Chapter 7 Troubleshooting the Cisco Unified IP Phone
General Troubleshooting Tips
Step 5
From Cisco Unified CallManager, select
Device > Phone
and verify that you have
assigned the correct MAC address to this Cisco Unified IP Phone.
To determine the MAC address of a phone, see the
Address of a Cisco Unified IP Phone” section on page 2-9
Step 6
Power cycle the phone.
General Troubleshooting Tips
provides general troubleshooting information for the
Cisco Unified IP Phones.
Table 7-1
Cisco Unified IP Phone Troubleshooting
Summary
Explanation
Daisy-chaining IP phones
Do not connect an IP phone to another IP phone through the
access port. Each IP phone should directly connect to a switch
port. If you connect IP phones together in a line
(daisy-chaining), a problem with one phone can affect all
subsequent phones in the line. Also, all phones on the line share
bandwidth.
Poor quality when calling digital cell
phones using the G.729 protocol
In Cisco Unified CallManager, you can configure the network
to use the G.729 protocol (the default is G.711). When using
G.729, calls between an IP phone and a digital cellular phone
will have poor voice quality. Use G.729 only when absolutely
necessary.
Prolonged broadcast storms cause IP
phones to re-register
Prolonged broadcast storms (lasting several minutes) on the
voice VLAN cause the IP phones to re-register with another
Cisco Unified CallManager server.
Содержание 7902G - Unified IP Phone VoIP
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