Getting Cisco phones working with asterisk may seem like a daunting procedure; getting SIP firmware installed on the phone, loading up the the firmware files in the tftp server, fearing that you will somehow brick the phone by an incomplete firmware upload…But I am here to reassure you that once you understand how Cisco phones update themselves, the fear and trepidation will subside.

In fact, Cisco phones are simple. They just need a tftp server to update its firmware and it doesnt even have to be located on the asterisk/phone system itself. 7940/60 Cisco phones update in two stages. The bootloader, then the application. Once the bootloader is upgraded, all passwords and networking information on the phone will be wiped out. But what is essential in upgrading these phones is a DHCP server with option 150 enabled – an option to auto-provision the tftp server ip address when the DHCP server hands out the regular ip address to the phone.
Without an auto-provisioned tftp server address, the phone will only complete half the upgrade and come up with an error message of “protocol application invalid.” This just means that the phone could not complete the second half of the upgrade and needs the tftp ip address to be specified. Only problem is since there is no application running, there is no place to specify the address! Thank goodness for DHCP option 150 which does this for us when the phone grabs an IP address after loading the bootloader.

Below are instructions to upgrade/convert any Cisco 7940, 7941, 7960, 7961, 7970, 7971, 7942, 7962, 7945, 7965 IP phone to any firmware you want from the Cisco web site (SIP/SCCP), and to recover any cisco phone which may have screwed up somehow while upgrading firmware (like if you get the protocol application invalid message).

Step 1: Download Cisco phone firmware
Cisco may require you to have a smartnet contract before you download the firmware, but if you do not have one, there are firmware files available on the internet. Ive provided two sources below.

a. Goto http://www.cisco.com/ and create a login if you do not already have one. Download the firmware for the specific phone you are using. (if cisco doesnt allow you to download the firmware, check here: ftp://ftp.itl.ua/pub/cisco/ip-7900ser/ or http://radiotwenterand.nl/~graver/cisco/SIP-7960/ for phone firmware).

b. Download the .zip file and extract it to a directory. If you are downloading an older version of the SIP/SCCP firmware and it only comes in a .cop file extension. Just rename the extension to .tar.gz and extract it to a directory using winzip or winrar.

You will have several files in this directory. If you just have one, you must remember to extract all the files.

Step 2: Download and configure the DHCP/TFTP server
We are going to use a windows based machine and load tftp/dhcp software on it which will make our windows machine a server for our phones.

a. Go here to download the tftp/dhcp server – http://tftpd32.jounin.net/
Download and install version 3.23 (<–YOU MUST DOWNLOAD AND INSTALL THIS VERSION. I have had many people complaining about their phones not obtaining a correct ip address and also the files not being sent correctly. Every one of these problems was due to using the incorrect version and/or having their firewall on).

b. You will also have to configure your windows machine to use ip address of 192.168.1.1 and subnet mask of 255.255.255.0.
Youll configure this tftp server to host the upgrade files via tftp server (theres an option to configure the working directory in the program to use for the stored firmware files on the windows machine – this must be set correctly!).

c. Under DHCP server within the tftp32 program, enter the following and click SAVE:

-IP pool starting address as 192.168.1.2
-Size of pool as 250 (if doing multiple phones, this just makes sure your phones are able to receive an ip address)
-Default router as 192.168.1.1
-Mask as 255.255.255.0
-Additional option, enter 150 in the first box, then 0x0101A8C0  in the second box (this number is 192.168.1.1  in Hexadecimal).

3. Putting it all together

a. Now, there are a few things to consider when upgrading 7940/7960 cisco phones (these steps below dont apply to the 79×1/79×2/79×5 java based phones, if you have one of these, just do steps d. and e.). But the rule of thumb, is that if you have SCCP on your phone youll need to use a XMLDefault.cnf.xml file to specify the firmware load information tag by which the phone can know what load it should install. For the rest of this guide I will just assume you want to convert SCCP to SIP.

b. The easiest way to get SIP on your phone is to install a universal application bootloader. Ive found that SCCP version 8.0.9 (P00308000900) has the most compatible loader which easily allows swapping between current SIP and SCCP loads without a hitch. So the best thing to do is to upgrade your SCCP phone with a newer SCCP load before switching over to SIP. If you have a very old version of SCCP, you will find that you cannot immediately upgrade to this version. If that is the case, just load version 3 (P00303010102), then load to version 5 (P00305000500), then jump to version 8.0.9 (P00308000900). To do this you have to download those firmware versions and just extract them all into one directory.

c. Now download and place this file into your firmware directory. XMLDefault.cnf.xml (right click on link…’save target as’ – this file contains the text below)

<Default>
<callManagerGroup>
<members>
<member priority=”0″>
<callManager>
<ports>
<ethernetPhonePort>2000</ethernetPhonePort>
<mgcpPorts>
<listen>2427</listen>
<keepAlive>2428</keepAlive>
</mgcpPorts>
</ports>
<processNodeName></processNodeName>
</callManager>
</member>
</members>
</callManagerGroup>
<loadInformation>SCCP40.8-3-1S</loadInformation>
<authenticationURL></authenticationURL>
<directoryURL></directoryURL>
<idleURL></idleURL>
<informationURL></informationURL>
<messagesURL></messagesURL>
<servicesURL></servicesURL>
</Default>

After you have downloaded the file, edit the loadInformation tag within the XMLDefault.cnf.xml file with the firmware you want to install on your phone. Do not add the file name extension, just the name of the file (ig. <loadInformation>P00308000500</loadInformation>). Save and proceed to the next step.

d. Next plug in the phone by crossover cable or ethernet switch to the computer you are running this server from (make sure you disconnect any device attached to the network which resolves an ip through dhcp, as this will conflict with any other dhcp server on the network).

e. Power Cycle the phone and clear the configuration by holding down the # key and then plugging in the phone. After all the lights cycle on the phone, release the # key and press 123456789*0# followed with the 2 key (if you are using a 79×1, 79×2, 79×5, 7970 phone, plug the phone in and hold the # key till the extension lights blink amber…then press 3491672850*#. The lights will turn red, but if they dont, repeat this step. The phone will then wipe the flash and load whatever firmware is specified in the tftpd32 directory – if the phone just keeps downloading the term.defaults file constantly, just do an incremental upgrade to the firmware version that you want).

This will clear all settings on the phone and set it to defaults. Upon reboot, the phone will grab an ip address from the dhcp server on the windows machine running the dhcp server. Tftpd32 will also assign an ip address for the tftp server to the phone using option 150, and the phone should start pulling down files from the server after it obtains an ip address.

f. If you are doing an incremental upgrade to get to version 8.0.9, just keep editing the XMLDefault.cnf.xml file with the next version of firmware and save, then reboot the phone (after it has completed loading both the bootloader and application). The phone should find that it needs to upgrade itself until you stop editing the file with new firmware information.

g. After the phone gets to SCCP version 8.0.9, all you have to do is just download the version of SIP firmware you want, and then extract it into a seperate directory. Point the tftpd32 program to use that directory, copy the XMLDefault.cnf.xml file to that directory and edit the loadInformation tag with the POS-xxx filename which is located in that directory and  reboot the phone. The phone will automatically switch over to loading the SIP firmware.

You can check the events viewer within tftpd32 to ensure that the phone is grabbing the necessary files and getting an ip address. The 79×1/79×2/79×5/7970 phones take a bit longer to fully complete the flashing process since they use more numerous and larger files than the 7940/60 series phones. If the phones just sit like they arent doing anything, wait a bit longer and they should come back up. Its not uncommon for one phone to take up to 4-5 minutes to complete the entire process.

Thats all there is to it, and now that the phone has a good universal application bootloader, you will have no trouble switching between SCCP and SIP by just pointing the phone to the appropriate directory.

If you have any questions, feel free to send me a message on my contact page, if you get really stuck I can also provide these services remotely.