Startup Ooma will start selling a $400 box in September; after you’ve purchased the box, you’ve got free phone calls forever, according to press coverage.

Frankly, I don’t understand this hype. It sounds as if Ooma is selling “Skype in a box” — a hardware version of what Skype offers, a peer to peer network for telephony. True, it’s a standalone box, allows POTS backup, and allows connection to your standard phones, all of which is worth something.

But I fail to understand the business model. How will the sale of one box allow them to provide infinite free PSTN connectivity? Sure, they’ll charge for international calls, but something doesn’t sound right; outbound PSTN calls cost money, and the ability to accept inbound PSTN calls costs even more. That can’t be financed by a single sale of a single box.

So my best guess — since Ooma’s web site doesn’t say, and the mainstream press (non-technical, e.g., Mossberg et. al.) seem to be oblivious to VoIP-to-PSTN problem — is that Ooma is a hardware version of Skype. They’ll sell PSTN numbers to receive inbound calls. They’ll sell international LD minutes. And if they go under, that $400 box won’t be able to connect to the PSTN any longer.

Edit, 2007-08-02: I’ve just learned/re-learned that Jeff Peck (see his comment below) is the Principal Architect at ooma. Since I happen to know from personal experience that Jeff is (a) very, very smart and (b) very, very competent, I suspect I will have to re-think my opinion of ooma…