Internet By Light Promises To Leave Wi-Fi Eating Dust (yahoo.com)

schwit1 writes: Connecting your smartphone to the web with just a lamp - that is the promise of Li-Fi, short for 'light fidelity,' which features Internet access that is 100 times faster than Wi-Fi. French start-up Oledcomm demonstrated the revolutionary wireless technology at the Mobile World Congress, the world's biggest mobile fair, this week. As soon as this smartphone was placed under an office lamp, it started playing a video. The big advantage of Li-Fi is theoretical speeds of over 200 Gbps.

Comments

Ceiling lights

[DrYak]

You need line of sight

Yes, but don't think "antena" (like having a single light source in a room to which one would need to perfectly align a corresponding transmitter on the smartphone).

Think "lightbulbs". As in every single energy-saving LED light-bulb on the ceiling of the office openspace is a LiFi transmitter.
Most often, a phone is left in plain sight on the surface (on the desk, etc.) so its FOMO-owner can quickly glance at it to check for alerts/e-mail/tweets (I think I'm the only alien keeping my phone in a protective holsted on the belt instead of obsessively needing to check my phone like anyone else).

So most of the time a phone is exposed to light comming from the lighting system and thus could take advantage of high-speed LiFi down-stream.

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The LED and light bulb industry is facing a small problem : LED-based energy-saving bulbs are so durable and low energy, that one barely needs to replace them. As the older technologies (incandescant or CFL) are progressively replaced, the demand for LED bulbs will get lower and thus the market opportunities of LED bulb maker.

So that's why they need to find other incentive for people to buy newer one. Overload them with new features!

Hence why the recent surge of "connected bulbs" that can be turned on or off from an App, with App-controlled colour, with colour conected to the TV's ambilight feature, etc...

And thus, of course, with no surprise, TFA mentions that Philips (a non negligible LED bulb maker) is also showing interest about LiFi bulbs.

Re:Ceiling lights

[Grishnakh]

It's completely impossible for this technology to actually work.

For one thing, it would only be one-way: from the light bulbs to your device. There's no easy to go the other direction.

But aside from that, it's just plain impossible: for your light bulbs to transmit LiFi, they would need a high-speed data connection to them, presumably gigabit Ethernet. This means that you would have to rewire your house to have Ethernet going to every single lightbulb, plus a giant 48-port switch somewhere connecting all these Ethernet lines to your router.

That isn't going to happen. The cost of the hardware alone is going to be high (24- and 48-port switches aren't cheap, though I guess you could make cheaper versions since they really only need to be transmit-only and don't need to actually switch data between all the bulbs, just distribute it), but the installation cost would be astronomical on any existing building. A WiFi router, OTOH, is dirt cheap and only needs to be installed one place, and will generally give you coverage all over your house.

Re:Ceiling lights

[ceoyoyo]

You wouldn't use a switch. The easiest way to do it would be to install some DC LED lights, powered by a single DC power supply somewhere. DC strip lights currently do this, and it's more efficient than having a power supply built into each bulb, so it's probably the way of the future anyway. You'd run ethernet to the DC power supply, which would modulate the power to all the lights. You could wire up all the lights in your house to broadcast a single signal (one port on your router) or you could wire up each room with it's own channel if you wanted more bandwidth. You COULD have separate channels serving individual bits of a single room, but you'd probably only do that if you had very special, high bandwidth needs.