Dynamic Host Configuration Protocol Server Interactions - Cisco 7925G Administration Manual

Dynamic Host Configuration Protocol Server Interactions

Related Topics
Phone Startup Process, on page 64
Dynamic Host Configuration Protocol Server Interactions
Dynamic Host Configuration Protocol (DHCP) is a communications protocol that lets network administrators
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 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, as
shown in the following table.
Table 10: DHCP Settings Priority
Priority
1
2
3
4
If DHCP is disabled, the Cisco Unified Wireless IP Phone uses the network settings in the following table to
perform the phone provisioning bootup process. You must configure these static parameters for each Cisco
Unified Wireless IP Phone.
Table 11: Static IP Addresses when DHCP is Disabled
Static Setting
IP Address
Subnet Mask
Cisco Unified Wireless IP Phone 7925G, 7925G-EX, and 7926G Administration Guide
38
DHCPsettings
DHCP option 150
DHCP option 66
SIADDR
ciscoCM1
Description
IP address, the unique identifier assigned by the system administrator for the
phone.
Used to partition the IP address into a network identifier and host identifier
so that TCP/IP can distinguish between them.
VoIP Wireless Network