I have a boot issue in Cisco IP Phone "Protocol Application Invalid." So I want to update my firmware.
I made my PC as TFTP and DHCP Server and connected my PC and IP phone in same vlan, but it is not getting IP address from DHCP.
The 7940 IP phone fails to perform the boot process correctly this problem could be
When you examine the sniffer trace between the DHCP server and the phone, you can identify that the phone accepts a DHCP offer from the data VLAN (the native VLAN) instead of the voice VLAN. full resolution for this problem could be found in this article IP Phone 7940/7960 Fails to Boot