Describe Cisco IP phone boot up procedures.
1. Switch sends power to IP phone, using 802.3af.
2. Switch delivers vlan info via CDP (voice VLAN)
3. IP phone sends DHCP request, DHCP delivers IP add and Option 150 - (TFTP server IP address)
4. IP phones contacts TFTP server and gets config file and firmware
5. Based on config file, IP phone registers with call processing server (subscriber server 1,2,3 then start again).
Small deployments have CME being the call processing server.