Why are there many products for in-home power-line computer networking, but nearly nothing for phone-line networking?
Naively I would think that running a LAN over the phone wires that are already in my house would be ideal. Of course it would not be as good as CAT 5 arranged in a star topography with a switch in the middle. But the phone is already designed to carry data, and all the jacks on the same line already are electrically connected. I don't even have phone service in my apartment so I wouldn't even need to deal with "interference" from a phone. The phone line can already carry DSL, which is slow by today's standards but surely is more reliable than bad WiFi.
Or, you can run a LAN over power lines. People complain that performance varies depending on whether the sockets used are on the same phase or in the same circuit. Other possible interference sources include refrigerators, air conditioners, compact fluorescent bulbs, hair dryers--in other words, common things to plug into electrical sockets.
My searches revealed something called HomePNA
, sort of the industry group to promote phone-line networks. But there are practically no products out there that actually do it. Meanwhile there are tons of power-line products, which some folks say work great and others say have problems.
So why are there so many power-line products but no phone line ones? Is the power line better for data than the phone line--seems odd to me, seeing as the phone line was actually intended to carry some data, no matter how slowly?