One of the more frequent complaints that I’ve heard from people dropping their POTS line and moving to pure VoIP is that their TiVo stops working. TiVos have a modem in them. They need to download program guide information at least once every two weeks, and modems don’t work well over VoIP. There are ways around this–newer “Series 2” models have a USB port and support wired and wireless Ethernet adapters, and older models can be hacked with “TiVoNET” cards that provide an internal Ethernet port. The problem is that TiVoNET cards are expensive and require opening your TiVo and voiding its warranty.

I think I have a unique way around this. It requires a local Asterisk server, a spare FXS port, and a modem, but I don’t see any obvious reason why it wouldn’t work. Since I have a series 1 TiVo and I’d like to drop my home phone line, I’ll probably check this out soon.

Here’s what needs to happen: 1. Connect the modem to your Asterisk box’s serial port. Install a getty that understands PPP (I’ve used mgetty in the past), and configure PPP to allow users to connect without a password. Turn logging up as high as possible. 2. Connect the modem to a dedicated FXS port on the Asterisk server. 3. Plug your TiVo’s modem into a different FXS port on the Asterisk server. 4. Force a connection attempt on the TiVo. Watch Asterisk’s logs to see what number it’s dialing. 5. Set up your dial plan in extensions.conf to map TiVo’s phone number onto the modem’s FXS port. 6. Have the TiVo dial again. It should connect to your modem instead of TiVo’s servers. 7. Using the PPP logs, fix things so that it actually logs in correctly. 8. Force another connection. At this point, it should log in and start exchanging IP packets with TiVo’s servers. Verify that it’s able to complete a full download. 9. Turn down logging on pppd.

It’s not particularly simple, but it should work, and you can do it without adding hardware to your TiVo. You’ll have to purchase at least one extra FXS port, possibly two, and they start at $50 for two and go up from there. Since TiVoNET cards start at $70 or so, this may not be a great deal, but it’s definitely good for hack value.