
'Li-fi 100 times faster than wi-fi' - grahamel
http://www.bbc.co.uk/news/technology-34942685
======
superuser2
That's nice, but my 5-year-old 802.11n WAP still has ~20x the bandwidth you
can buy for any amount of money at my house. Faster WiFi is not particularly
interesting for consumers unless they're also getting faster ISPs.

~~~
nitrogen
Has the entire world forgotten what a hard drive is? What LANs are? Good
grief! You can transfer data on a network without sending it to Dropbox first!
Faster local networks have _tons_ of uses beyond just slaving them to
someone's walled garden.

~~~
spdionis
Except the UX of that is horrible. I'd have no idea how to set-up that and I'm
sure it would take me at least a couple of hours...

~~~
nitrogen
Windows can automatically set up a "home group". OS X can use a network for
Time Machine. In Linux as well, you can typically right click a folder and
choose "share". You can use a Chromecast. You can use Plex or Kodi/XBMC. You
can use AeroFS, PogoPlug, Owncloud, or any of a number of commercial NASes.
You can live-stream games using Nvidia tools or Steam. You can use IP cameras.
Etc. ad infinitum.

None of these have a UX that is appropriately described as "horrible".

~~~
superuser2
\- Time Machine is a background process so network bandwidth is not super
important.

\- _Can_ you even Chromecast content that isn't from the internet? I have one
and use it with Netflix all the time, but that's news to me.

\- Typical living-room fare is only getting into XBMC or onto a hard drive/NAS
if it's been BitTorrented. Streaming rules the day for me and for most people,
it seems. (Not all of it is legal, of course, but people seem to vastly prefer
illicit streaming sites to torrent trackers and clients.)

\- OwnCloud is substantially more useful on a VPS so that you can access it
from anywhere. Time Warner blocks incoming connections to its residential
cable modems, last time I checked.

\- IP cameras tend to be low resolution, low framerate, or both.

Of course local networks have their uses. What I contend is that very few
people are actually constrained by the ~300Mbps of 802.11n.

Maybe the real application is business networking, so that remote desktop
workstations could be practicable without wired networking.

~~~
Veedrac
It'd be a bit strange for tab streaming to go over the internet, and there
certainly are apps that stream local videos. Maybe they do go over the
internet, but I wouldn't just assume it.

~~~
SoreGums
>You can Chromecast local content via Videostream[0] for Google Chromecast.
You can even control the Videostream host via mobile app[1].

The issue with Chromecast is you still need an internet connection to get the
app onto the Chromecast to stream the video to it... I was using this and it
was awesome! Then things happened and I was stuck on a shaped 256kbps
connection and Videostream stopped working reliably. Switched to Kodi on the
Remix Mini, works well, though not as good as Videostream did...

------
delbel
Every couple of years I hear about this. Then it gets forgotten, and re-
invented. Each time it never manifests into a real product. That reminds me, I
think we're about due for another rehash of the "Voyager leaves the solar
system" article, anyone? Or another segment on the local news where they say
"Scientist find [wine|beer|cheese|coffee|nuts|fat|red meat] [good|bad|healthy]
for you" article.

~~~
TeMPOraL
Don't forget that we're overdue for another miracle development in batteries,
as well as the next iteration of sprayed-glass coating that turns everything
waterproof and bacteria-free.

~~~
cooper12
This is one of my biggest pet peeves. Every week on the news you hear about a
miracle graphite battery that is super thin and has 500 times the capacity.
The first time I was excited, the second disappointed, and every other time I
just sighed. I'll believe it once it's hit the market. I don't understand why
the news reports experimental research just because it's novel. Of course the
researchers will play along because it makes their work seem important,
stroking their egos and helping them get future funding.

~~~
dzhiurgis
All I can think now is "Will a new battery size of rolodex be able charge your
iPhone 400 times and power your electric car drive from Folkestone to Stoke-
on-Trent?"

And "New solar panel technology powers 30 middle Atlantic households or 400
French sheds."

------
djmdjm
There was an IR physical layer defined for 802.11 last century, but it didn't
go anywhere.
[http://dl.acm.org/citation.cfm?id=2289301](http://dl.acm.org/citation.cfm?id=2289301)

~~~
rdtsc
Interesting, I just remembered about 10-15 years ago, I had laptop with
"infrared" support. Never quite knew what that was for. But one day noticed in
the lab I was working the HP printer had an IR window, after a quick search on
the net, sure enough I could print a few pages using IR from my laptop. That's
all I did with it and had forgotten it since.

~~~
thrownaway2424
Apple products used to (pre-2012) come with an infrared remote control. You
could use the port for anything. I used mine to record the secret codes that
the TV repair guy was punching into my set.

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Veedrac
To all the "lab tech never actually arrives" skeptics, it's worth noting that
12 years ago this was a thing:

[http://news.nationalgeographic.com/news/2003/03/0318_030318_...](http://news.nationalgeographic.com/news/2003/03/0318_030318_internet.html)

In my opinion, expect to see VR as the first consumer device to pick this up -
it's too bandwidth limited for today's wireless and sorely wants not to be.

~~~
onion2k
Why does VR need more bandwidth? Surely it's just a video feed in and some
telemetry data out. Isn't latency more of a problem?

~~~
moogly
First of all, you need a lot higher refresh rates, because you tie in your
ocular-vestibular system which is very sensitive, compared to the visual
feedback required to be comfortable sitting in front of a monitor. It's still
unclear where the upper limit is, but the lower is probably at least 120 Hz.
The consumer devices being released soon are running at 90 Hz, and that's the
bare minimum. I've heard "1000 Hz" coming out of Michael Abrash's mouth, but
that was somewhat of a hypothetical number.

Secondly, higher resolution. You'll want at least 4K in the near future,
because with a lower resolution display that close to your eyes, you'll
discern individual pixels and the actual space between them (causing the
infamous "screen door effect").

~~~
Veedrac
Even further, strict latency requirements on an already-busy system prevent
you from doing any interesting compression.

------
jepler
Since fiber optics work just dandy, clearly getting your source to switch on
and off at the requisite rate is not the trick. But if you're not shining down
a fiber optic cable, you have the problem that intensity decreases as the
square(?) of distance from the emitter; and that your multipath problems
become a lot more pronounced.

~~~
mmmBacon
These 2 things are created in different semiconductor technology (materials)
that have quite different properties. Most communications are either in GaAs
for NIR or in InGaAS/InP for mid IR. Visible stuff here is generally a large
GaN die pumping a phosphor material. As the size of the die increases so does
its capacitance which ultimately limits the rate at which the signal can be
modulated or the brightness of the source. Additionally in the visible you use
Si detectors which are slow due also to their large capacitance. So I think
it's unlikely you could ever realize 224Gb/s unless you were using WDM
(wavelength multiplexing).

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motosynthesis
How do you request the data to be transferred? This magical system is starting
to get an awful lot more complicated.

~~~
Sanddancer
Beamforming. The other articles I've seen on using the visible spectrum for
communications mostly discuss sending to a mostly stationary object. It's not
great for general purpose, but as a wiring replacement, can be rather useful.

~~~
motosynthesis
i'm no computer scientist, but don't i have to request information in order to
receive it? What i mean is, do i have to attach a LED light to my laptop to
request the data from the LED in my roof?

~~~
Sanddancer
Yes and no. One could just receive broadcasted data -- a monitor on the other
side of the room really doesn't need to send much info back. For a laptop, one
wouldn't necessarily need to request data via an LED, the requests could be
made over some other medium, like traditional wifi, with the responses coming
from the LED.

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p1mrx
1Gbps is not 100X faster than Wi-Fi, unless you're talking about 802.11g under
marginal conditions.

~~~
davb
I've come to take the BBC's tech reporting with a pinch of salt.

~~~
TeMPOraL
Given that everyone else's reporting is worth the same or even less, I wonder
where do you still find salt for all of that? I've run out of mine long ago.

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schappim
Great, but you can't use it in the dark! Perhaps they could fix this with
infrared?

~~~
AYBABTME
or UVs..!

~~~
snerbles
...then wireless networking really will cause cancer.

~~~
the8472
maybe a deep violet right at the edge of the visible spectrum? all you would
see is a faint glow

~~~
drdaeman
I'm not sure but I heard short wavelength (blue/violet) visible light has most
impact on circadian rhythms.

If it's indeed the case, insomnia or any other kind of sleep disorder is not
worth it.

------
jaybna
Imagine if someone used ultrasonic sound in conjunction? Ultra fast networking
and witless charging. Oh wait, that won't work....

