A while back a friend asked me how I did this so he could too. For cable modem subscribers, the savings is about $250 per year. You also get greater control over blocked numbers, forwarding, and voicemail. I purchased an Obihai VOIP router on Amazon for $40 to get started. If your home network doesn’t have an extra ethernet port, you there’s a version with an integrated router.
Here are the rest of the steps: