If you still rock the bunny ears we salute you. But odds are, you probably get TV one of two ways: Cable or satellite. There's a newer way: IP, that is Internet Protocol, TV-in this case, the TV delivered over the internet by your phone company. Verizon and AT&T push FiOS TV and U-Verse, respectively, in select regions of the country where their fiber networks have been built out. (Update: As has been pointed out, FiOS TV isn't actually IPTV, my bad.) In a lot of ways, it's the TV of the future-in part because most of you can't get it yet. Beyond that, the technology that delivers it to your home, as well as who is doing the delivering, opens up some pretty sweet new interactive possibilities. And even for regular old boob tubing, the way it's architected means its good for HD buffs.
But first, the basics. The difference between the TV you're used to and this fancy IP
TV stuff is that IPTV is delivered to you like any other data sent over the internet-in data packets. You even plug an Ethernet cable into your receiver box/DVR. Of course, the internet's a messy place with lots of muck bouncing around the pipes and you'd be really pissed if the Yankees game stuttered or crapped out, so this is all running on the telco's "walled garden" network with a fat, dedicated lane for video. (Your internet service, which is bundled since it's running on the same network, runs on a different lane, delineated by quality-of-service, or QoS, protocols.)
Now that that's out of the way, back to why its good for HD. With a standard cable setup, the channels are basically always being piped into your home, whether you're watching or not. To add more channels, they've gotta compress 'em down farther or open the pipe up, especially since HD eats up a lot of bandwidth. Since IPTV is sent in regular ol' data packets and the system is two-way (the nature of internet protocol), they're basically only sending what you ask for, when you ask for it. So theoretically, they could offer way more HD channels than cable, since they're not as limited here. Also, like that mythical Xbox 360 IPTV box, the number of streams you can watch/record simultaneously is basically only limited by your bandwidth.
The two-wayness of the infrastructure is another point of awesomeness. It can be used for actually useful interactivity-one of AT&T's apps for the Olympics can bring in a stats feed you can check out while watching the game. Or regular internet video, like YouTube, can be piped in and integrated with the other video on your box. It's all just regular data over standard internet protocols, so there's a lot of flexibility to do stuff you simply can't with a traditional setup.
The problem is that building the infrastructure necessary for IPTV service is slow and expensive, largely cause it requires a heavy fiber optic component. Verizon runs fiber all the way to your door (which is why it can offer those crazy FiOS internet speeds), while AT&T runs it to the node, which you're then connected to with copper and (which is why U-Verse internet is slower). So right now, both have puny subscriber numbers-1.2 million FiOS TV customers, and a scant 379,000 on U-Verse TV.
Still, there's a lot of potential in IPTV, even if it's taking forever to get to your doorstep. AT&T actually showed me some of the stuff that could be at your door in the 6-9 months-and beyond-and it's definitely worth getting excited about. We'll be telling you all about it later.
Something we missed, or you still wanna know? Send any questions about IPs, TVs, chewing gum or anything else to firstname.lastname@example.org, with "Giz Explains" in the subject line.