DirecTV has been using MoCA for some time to implement their whole home DVR. I've been a DirecTV subscriber for years. In my previous house, I had easy access to the locations I had the TV and it was trivial to pull the Cat5 cable to those locations. In my new house, however, a number of issues made it tricky to pull new cable. The finished basement sealed in many of the cable runs without a nice pull-string. The cables were run through the joists in a point-to-point manner. The exterior walls of the house are insulated with hay bales. These are great for insulation, but impossible to run electrical cable though (and even if it wasn't, fire codes prevent it). Finally, the attic has lots (48") of blown in cellulose insulation. Great for my heating bills, but not so good for access.
I went ahead and had my DirecTV professionally installed. As a life long DIY person, this was tough for me. However, time was short and this saved me a day of dinking with it. The installers have gotten much better since some bad experiences I had 15 years ago now. They got me all setup. I have a nice new HR24 in the main TV area, and a HR23 from my old house. Sadly, I had to let go of the HR10 which I'd been pulling video off of for years. Such is the price of progress.
In the basement, they installed a DECABB1MR0 (Direct TV Ethernet to COAX adapter). This is a simple device that connects to the cable plant coming off the SWM to your ethernet. They connected this so the HR23 and HR24 would be connected to the internet. This technology is called MoCA, and it drives much of the home sharing. The HR24 has MoCA built in, but the HR23 didn't. The cable guys installed the HR23 directly into a slightly different device (a DECA-II that was powered from the HR23 box and provided a single ethernet port). They told me it was the only way it could work. However, they were mistaken. I now have a ethernet switch with the DECA-II, my HR23 and my TV with Netflix. This works great. It is a bit anti-climatic, though, since I also had a cat5 port near this TV I could have used instead. But since I needed the router anyway, I thought I'd save myself some time and trouble troubleshooting the Cat5 port (all of them in this house have been wired wrong) and use this setup. I've watched movies from Netflix, DirecTV shows, shows recorded on my HR-24 as well as on-demand shows streamed over the internet. It's all good.
Next, up, I had to tackle the HR-24. There's no power for the deca-ii adapters coming off this box. And it didn't occur to me until I was writing up this blog post I could have just used a deca-ii by switching the port in the SWM from the unpowered to powered port and plugged the ethernet directly into my sony player. However, I was able to do the next best thing. I got a second DECABB1MR0 on ebay for $10.00 or so. I got a good 2-1 splitter (3.5dBm loss) and some good 1' RG-6 cables online. I was then able to wire the cable from the wall into the splitter. One leg went to the HR-24. The other leg went to the deca to go onto my sony player. The splitter did result in a small loss of signal to the HR-24, but all the signal strength levels look good on the setup screen. I've been able to stream Netflix off the Sony DVD player as well. I've not yet seen how well this responds in snow and ice.
Anyway, just a simple connection of different technologies. I learned these devices are nice MoCA bridges, and you can get decent performance over MoCA (decent enough for streaming video), but that the ping times are much greater (3-4ms rather than 10-100us that I'm used to seeing over GB ethernet). The technology is a bridging technology, with multiple devices allowed on either side of the bridge. The 3dB splitter worked better than I feared it might and is a simple way to connection. The powered port option should be kept in mind for future expansion if and when I add another receiver.