When the phone boots, it can get the tftp server address (in our installation, it points to the CTI server) from the dhcp server and downloads its firmware, global config and specific phone config file (XXXXXXXXXXXXcfg.cfg where X's equal MAC of phone). Ours are the 86XX series phones, but I presume the same will hold true for other models...
Sample details included below...
# This is a sample a MAC config file for an individual 8662/8662E V1 phone
#########################################################
# Axxess IP mode Settings
#########################################################
# IPRC's IP address
# Must be named XXXXXXXXXXXXcfg.cfg Where XX is the Mac address of the IP Endpoint
cc_srv_ip: 192.168.XXX.XXX
#########################################################
# VLAN ID Settings
#########################################################
# This is the VLAN ID
vlanid: 100
# This is the PC port VLAN, not needed with our trunking setup
#dwnlnk_vlanid_1: 25
Global TFTP file:
# Any settings that the phone does not find in its
# device-specific configuration file, the phone will use
# the global configuration equivalent. If the setting is
# not in the device-specific file or the global file, the
# phone will not change its local setting.
#
# A line beginning with # denotes a comment.
# Commented lines are commented because we would rather
# pull the settings from the device-specific config file
# or let the phone keep its local setting.
#########################################################
# Network Settings
#########################################################
# DHCP -- 0 = disabled; 1 = enabled
dhcp: 1
# Put static IP in the device-specific config file.
#static_ip: 192.168.200.201
#static_snm: 255.255.255.0
#static_gw: 192.168.200.1
# The IP of the TFTP server.
# Could also include a path from the TFTP root.
tftp_url: 192.168.19.2
# The TCP port number for the phone's web server.
http_port: 8080
# Operation mode -- 0 = SIP; 1 = Axxess IP
opern_mode: 1
# Phones will pull this config file every 3600 seconds (time frame for 7 days listed below)
update_interval: 604800
###################################################################
# This is used once to upgrade existing IP phones to V2 IP Phone SW
###################################################################
# This would upgrade an 8662/8662E endpoint from 1.01S, 1.0.31, 1.0.33, or 1.1.5 to 2.X.XX
8662_image_ver: HWID 3 2.2.00
8662_image_url: 192.168.19.2/bin/8662_2_2_00.bin
#########################################################
# Trace mode Settings
#########################################################
# Enable UDP debug and set the phones not to reset on exceptions
#trace_host:172.17.156.220
#trace_port: 6688
# Enable UDP log
# turn off resets on exceptions and assertions, enable UDP logging
# and sip logging
#trace_flags: 0x0e
#########################################################
# Axxess IP mode Settings
#########################################################
#This Line needs to be set in the device (MAC) specific setting since the IPRC card IP will not be
#the same for all phones
# IPRC's IP address
#cc_srv_ip: 192.168.XXX.XXX
#########################################################
# Software Image
#########################################################
#This is the V2 IP Phone Image
itphone_image_ver: 2.2.02
itphone_image_url: 192.168.XXX.XXX/bin/itphone_2_2_02.bin
