The Cisco ATA 18X series can run either SCCP, H323 or SIP voice protocols making it very flexible.
Another note of importance is that they do not support two ports running the G.729 codec simultaneously. If one port is using G.729, the other will use G.711. In this manual we are using a SIP firmware (ata_03_02_04_sccp_090202_a). If you want to update to other firmwares or perhaps protocols, I suggest you read the last 2 links provided in the resources section.
Take note that this firmware supports only SIP:
To upgrade the firmware do the following:
Step1
Query the IP address: By default the ATA gets the IP from DHCP. TO catch the IP simple connect an analog phone to either PHONE1/2 ports, pickup the phone, press the red light button on the ATA to get dial tone on the phone and after the prompt “configuration menu” press 80#, the system will read you the IP. If the IP is not valid, you must figure out and fix it at this point and then only proceed.
Step2
Use the IP you got from above and browse: _ATA_IP/dev. You must see a simple page like below. set the TftpURL parameter to the ip of your TFTP server.
Step 3
Untar this folder and copy the containing files in the TFTP root folder and then reboot the ATA. This is the whole firmware package.
After reboot wait until the LED indicator stops blinking. Then browse the IP again. The interface should be totally different now (see below)
Step 4
You can use this interface to modify your configuration from now on
Sources:
Upgrading Analog Telephone Adaptors (ATAs)
Asterisk User’s Guide to the Cisco ATA-186 v.2003062801