Using Cable Modems with Embedded ATAs with Asterisk

Ok here's the a challenge. I have just recieved a Motorola SBV5120 cable modem with two analog telephone ports. I didnt sign up for the cable phone service (of course) because I have my own Asterisk box. There is no configuration option on the internal modems config screens to configure these ports (at least as far as I can tell). I've searched the web and cant find any info about how to configure the ATA ports either. So I'm turning to the benovolent Asterisk gods to help me unlock this mystery. How can I can configure these ports to run with Asterisk?

Not sure how you put a screenshot on the wiki, but heres the main menu.

Configuration Manager
Status Signal Addresses Configuration Logs Help <=== menu options
This page provides information about the startup process of the Cable Modem. If there is a problem with
the startup, the word "Failed" may appear in the Status column. Should this occur, visit the Help area and
perform the Checkup procedures listed there. If the problem continues, click on the word "Failed" for more
detailed information about the failure, or call your service provider for assistance.
Task Status
Acquire Downstream Channel Done
Obtain Upstream Parameters Done
Establish IP Connectivity using DHCP Done
Establish Time Of Day Done
Transfer Operational Parameters through TFTP Done
Register Connection Done
Initialize Baseline Privacy Done
Status | Signal | Addresses | Configuration | Logs | Help
� Copyright 1997-2000

None of the settings seem to be configurable. Its more like info only.
Must be another page in their for the ATA stuff

Daniel: This cable modem's ports are configured by your cable provider, for what i know you cant configurate it by hand.

09-08-2005:
Well, this modem had appeared lately where I live too, and I've decided to take a wiff at trying to hack it. From the
documentation I couldn't gather if this a SIP device or some kind of other device. However, from the way it was provisioned
by the cable operator, I believe I can assume the following:

a. This modem is NOT a SIP enabled device.
b. This modem appears to be lacking the ability to manage it self, which most probably means that it uses MGCP as the signaling layer.
c. In order to configure it by the ISP, I had to give them the modem MAC address, which was then identified by their LDAP systems - which only strengthens point (b).

Anyone else wants to take a wiff at this one?

23-08-2005:
These modems don't use SIP. They use a special telephony service over PacketCable (google), so they're not really useful for us. Besides, they're configured through the DOCSIS configuration file that the modem gets from your ISP and you can't get between that.

24-08-2005:
This eMTA do not support SIP.
The signaling protocol used for VoIP is NCS, a MGCP variant specified by PacktCable. In fact NCS is very similar to MGCP.
As it was said, the config of the cable modem and the embebed MTA is done by the service provider. When you turn it on, it comunicates with a CMTS via DOCSIS and then it gets config files from dhcp and ftp servers. You can use a software named "Incognito" as configuration server. In most cases, Incognito sends a binary config file to the MTA (via ftp or tftp). I dont know how to generate this binary. In the lab I work, we asked Motorola to generate one for us. Incognito has other features, and using it I believe its possible to setup the MTA without using a binary config file. The purpose of the binary config file is mass configuration. Try to use the Incognito provisioning server.