Understanding Phone Configuration Files - Cisco 7911G - IP Phone VoIP Administration Manual

Chapter 2 Preparing to Install the Cisco Unified IP Phone on Your Network

Understanding Phone Configuration Files

Note
Cisco Unified IP Phone 7906G and 7911G for Cisco Unified Communications Manager 6.0
OL11954-01
Configuration files for a phone are stored on the TFTP server and define
parameters for connecting to Cisco Unified Communications Manager. In
general, any time you make a change in Cisco Unified Communications Manager
that requires the phone to be reset, a change is made to the phone's configuration
file automatically.
Configuration files also contain information about which image load the phone
should be running. If this image load differs from the one currently loaded on a
phone, the phone contacts the TFTP server to request the required load files.
These files are digitally signed to ensure the authenticity of the files' source.
In addition, if the device security mode in the configuration file is set to
Authenticated and the CTL file on the phone has a valid certificate for
Cisco Unified Communications Manager, the phone establishes a TLS connection
to Cisco Unified Communications Manager. Otherwise, the phone establishes a
TCP connection.
If the device security mode in the configuration file is set to Authenticated or
Encrypted but the phone has not received a CTL file, the phone will continuously
try to obtain a CTL file so that it can register securely.
If you configure security-related settings in Cisco Unified Communications
Manager Administration, the phone configuration file will contain sensitive
information. To ensure the privacy of a configuration file, you must configure it
for encryption. For detailed information, refer to the "Configuring Encrypted
Phone Configuration Files" chapter in Cisco Unified Communications Manager
Security Guide.
A phone requests a configuration file whenever it resets and registers with
Cisco Unified Communications Manager.
A phone accesses a default configuration file named XmlDefault.cnf.xml from the
TFTP server when these conditions exist:
You have enabled auto-registration in Cisco Unified Communications
•
Manager
The phone has not been added to the Cisco Unified Communications
•
Manager Database
The phone is registering for the first time
•
Understanding Phone Configuration Files
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