Cisco 7920 - Unified Wireless IP Phone VoIP, Administration Manual

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Chapter 2 An Overview of the Wireless Network
Components of the VoIP Wireless Network
2-18
Cisco Wireless IP Phone 7920 Administration Guide for Cisco CallManager Release 4.0 and 4.1
OL-7104-01
The phone first requests the configuration file SEP xxxxxxxxxxxx .cnf.xml, where
each xx is the two-digit lowercase hexadecimal representation of each integer in
the phone’s MAC address. If the phone cannot find this file, it requests the
configuration file XMLDefault.cnf.xml.
After the phone obtains the *.cnf.xml files, it requests a phone-specific profile
file. If a phone cannot find this profile file, it requests the appropriate common
profile file.
After the phone finds one of the profile files, or if it cannot find a profile file, it
continues with its startup process.
Related Topic
•
Understanding the Phone Startup Process, page 2-21
Interacting with the DHCP Server
Dynamic Host Configuration Protocol (DHCP) is a communications protocol that
lets network administrators manage and automate the assignment of Internet
Protocol (IP) addresses in a network. When an IP device is added to the network,
it must have a unique IP address. Without DHCP, the IP address must be entered
manually at each device. DHCP allocates IP addresses dynamically and reuses IP
addresses when devices no longer need them.
If DHCP is enabled in the network, the Cisco Wireless IP Phone 7920 uses the
DHCP scope settings in the DHCP server to perform the phone provisioning
bootup process. You must configure the settings of the DHCP server in the
Cisco CallManager network.
The DHCP scope settings include the following:
• TFTP server
•
DNS server IP address (optional unless using host names)
•
Pool and range of the subnet mask, IP address, and gateway
The priority of the DHCP settings for the TFTP server is unique to the
Cisco Wireless IP Phone 7920, as shown in
Table 2-3 .