Interacting With The Dynamic Host Configuration Protocol Server - Cisco 7925G - Unified Wireless IP Phone VoIP Administration Manual

Chapter 2 Overview of the VoIP Wireless Network
Related Topic
Understanding the Phone Startup Process, page 3-17

Interacting with the Dynamic Host Configuration Protocol Server

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 7925G 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:
•
•
•
The priority of the DHCP settings for the TFTP server is unique to the Cisco Unified Wireless
IP Phone 7925G, as shown in
Table 2-5
Priority
1st
2nd
3rd
4th
If DHCP is disabled, the Cisco Unified Wireless IP Phone 7925G uses the following network settings in
Table 2-6
for each Cisco Unified Wireless IP Phone 7925G.
Table 2-6
Static Setting
IP Address
Subnet Mask
Default Router 1
Cisco Unified Wireless IP Phone 7925G Administration Guide for Cisco Unified Communications Manager 7.0(1)
OL-15984-01
TFTP servers
DNS server IP address (optional unless using host names)
Pool and range of the subnet mask, IP address, and gateway
Table
DHCP Settings Priority
DHCP Settings
DHCP option 150
DHCP option 66
SIADDR
ciscoCM1
to perform the phone provisioning bootup process. You must configure these static parameters
Static IP Addresses When DHCP is Disabled
2-5.
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 TCP/IP can distinguish between them.
Identifies the gateway that provides connectivity to the IP network
beyond the subnet to which the phone belongs.
Components of the VoIP Wireless Network
2-15