The Cisco 7912 usually runs SCCP (Skinny Call Control Protocol) and is not very useful for our purposes because we run Asterisk with SIP based hardware.
After googling for a bit, I found SIP firmware for this model phone, CP7912080001SIP060412A.ZIP on Cisco’s site, but you need an account with them to download the file. If you don’t have an account, try googling the file name.
The firmware will be loaded from a TFTP server when it boots, so you will need to extract the zip file and place the 3 files from the zip file into the TFTP root folder. The files you need are:
Then you will need to set the TFTP servers IP address in the phone. There are 2 ways to do this, 1) set option 66 in the DHCP server, 2) set in phones network configuration menu.
To set the TFTP server IP address via the phones menu, go to Settings and then Network Configuration. Go down to TFTP Address and press **# to bring up the hidden edit menu.
The main problem I had with this phone was it was password protected, but I didn’t know the password. I tried the default password of 1234 but that didn’t work, so I had to factory reset it. While in the settings menu press **2 on the phones key pad (not all together, but one at a time).
After saving the TFTP IP Address, the phone will reboot. If you watch the TFTP servers log, you should see the phone downloading the files.
It’s a nice 1 line, super easy phone. My biggest complaint is there is no speaker phone and SIP options are very limited. The phone does have keyhole openings in the back of the phone to make mounting on a wall real easy.