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Cisco Unified Wireless IP Phone 7921G Administration Guide for Cisco Unified Communications Manager Release 7.0
OL-15985-01
Chapter 2 Overview of the VoIP Wireless Network
Components of the VoIP Wireless Network
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 3-18
Interacting with the DHCP Server
Dynamic Host Configuration Protocol (DHCP) is a communications protocol that enables network
administrators to manage and automate the assignment of 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 Unified Wireless IP Phone 7921G 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 Unified Communications Manager network.
The DHCP scope settings include the following:
•
TFTP servers
•
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 Unified Wireless
IP Phone 7921G, as shown in
Table 2-4
.
If DHCP is disabled, the Cisco Unified Wireless IP Phone 7921G uses the following network settings in
Table 2-5
to perform the phone provisioning bootup process. You must configure these static parameters
for each Cisco Unified Wireless IP Phone 7921G.
Table 2-4
DHCP Settings Priority
Priority
DHCP Settings
1st
DHCP option 150
2nd
DHCP option 66
3rd
SIADDR
4th
ciscoCM1
Table 2-5
Static IP Addresses When DHCP is Disabled
Static Setting
Description
IP Address
IP address, the unique identifier assigned by the system administrator
for the phone.
Subnet Mask
Used to partition the IP address into a network identifier and host
identifier so TCP/IP can distinguish between them.
Default Router 1
Identifies the gateway that provides connectivity to the IP network
beyond the subnet to which the phone belongs.