The Cisco IP phone boot-up process involves 4 key steps: 1. Inline power initializes the phone and powers on buttons. 2. CDP or LLDP-MED detects the voice VLAN and displays the configuration. 3. DHCP assigns the IP address and locates the TFTP server. 4. TFTP transfers the configuration file and firmware to fully boot the phone.

1. Cisco IP Phone Boot-up Process
(From www.cisco.com)
1. Inline Power (ILP)
Inline Power Initialization
On Phone: Mute, Headset, Speaker Buttons Are Illuminated
2. Cisco Discovery Protocol (CDP) or Link Layer Discovery Protocol-
Media Endpoint Discovery (LLDP-MED)
ILP Negotiation, Voice VLAN ID

2. Phone displays: “Configuring VLAN”
Phone settings:Settings=>NetCfg=>“Operational VLAN ID”
NOTE: LLDP-MED is supported as of IP Phone Firmware 8.3(3)
3. Dynamic Host Configuration Protocol (DHCP)
IP Assignment, TFTP Server Allocation, DNS (optional)
Phone displays: “Configuring IP”(DNS is optional)
Phone settings: Settings=>NetCfg=>“DHCP
Server”Settings=>NetCfg=>“IP
Address”Settings=>NetCfg=>“TFTP Server X”
4. Trivial File Transfer Protocol (TFTP)
Configuration File, IP Phone Firmware

3. From http://docisco.blogspot.com/2010/09/phone-boot-up-process-from-
wwwciscocom.html
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