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[sevenlayermuddle]

Wow, 100 times faster, that's 101 times the speed of WiFi.

http://www.bbc.co.uk/news/technology-34942685

Except, let's read the detail...

Li-fi can deliver internet access 100 times faster than traditional wi-fi, offering speeds of up to 1Gbps (gigabit per second).

Eh?  So, WiFi is limited to 10 Mbps.  Or at least, somebody told the BBC that it was, and they believed it, and gave that individual a huge splash of free advertising, funded by the BBC's income source, the licence payers. 

They go on..

It requires a light source, such as a standard LED bulb, an internet connection and a photo detector.

Err, why does it require an Internet connection, it's only replacing a local network?  And a 'standard' led bulb, really... like the one I bought last week, that was 'standard'?   And what about the uplink, my iPad has no LED light bulb at all?

I fully understand that the BBC may find it hard to field tech savvy reporters.   But if they can't manage to find a reporter with a basic comprehension of the technology they are discussing then, IMHO, they'd be best to just abandon the story.   

I'm not actually opposed to LiFi, it may have niche uses - such as in the near future as high speed satellite broadband becomes available aboard aircraft, if WiFi remains banned for safety reasons.   More likely, IMHO, the aircraft manufacturers will find a way, incentivised by revenue streams, of allowing on-board WiFi after all.

[burakkucat]

Thank you for providing the link. 

    For the reporting.

    Now why does my head hurt?

[sevenlayermuddle]

In fairness, since posting it has occurred to me... My IPad does of course have a light source (led I assume), behind the display.   I don't think my oversight changes anything but if it does, THAT would have been the story. 

[kitz]

If my memory serves me correct (possibly not) but hasnt li-fi been brought up and discussed on these forums before.  Possibly over a year ago, so I dont think the concept is that new.  I seem to recall it had several downfalls and although it may be useful in some instances its not ideal. 

[burakkucat]

If my memory serves me correct (possibly not) but hasnt li-fi been brought up and discussed on these forums before.  Possibly over a year ago, so I dont think the concept is that new.

Thinking about it, I do believe that you are correct. 

[WWWombat]

It looks like LiFi can achieve throughput even higher than 100x WiFi, but you have to be thinking *much* deeper than just one lightbulb...

LiFi has been around since 2011. Some history:
http://purelifi.com/what_is_li-fi/the-lifi-story/

That page also has some "myths", including the one about LiFi being 100x WiFi.
It looks like commercial LED bulbs are capable of 100Mbps, but faster stuff needs to be tuned better ... with RGB bulbs getting gigabit, and serious lasers getting 100Gbps.

The professor that started it all has this to say (yesterday) on the 100x thing. He both debunks the myth, and points out it isn't true when comparing like-for-like:
http://www.lifi.eng.ed.ac.uk/lifi-news/2015-11-28-1320/how-fast-can-lifi-be

But at the bottom, he then points out how much *more* LiFi can achieve - 1,000x as much, when considered "per square metre".

I'm thoroughly intrigued by the document linked near the bottom - modelling "optical access points" in a network in a room (ie lots of light bulbs), and applying cellular radio techniques to it. That results in their concept of "LiFi attocells" with a radius of around 3m; one picture is of a 20m x 20m room, overlaid with a 5x5 hexagonal cell pattern.

That concept - of being able to break the area down into many small cells - seems to be a key method for achieving the very high multiples of what LiFi can achieve over radio, "per square metre"

The only downside? Someone needs to be developing the backhaul... Fibre to the lightbulb?

[Ronski]

The only downside? Someone needs to be developing the backhaul... Fibre to the lightbulb?

That's what I was thinking, all well and good having these 'lights' capable of this speed, but we'll need network connections to each li-fi light fitting, which is not easily retro fitted. But this would be very good in new builds, or complete renovations, it should solve the problem of everyone fighting for some wireless space and also people hacking into your wi-fi.

[sevenlayermuddle]

For my own example of in-flight use on passenger aircraft, the external internet link is already available via commercial satellites, high speed broadband now being on offer.  I believe deals have been struck and  some airlines who will start rolling it out next year.  I don't recall seeing  any details of how it will be offered to passengers, i.e. perhaps via dedicated (wired) tablets, or if they'll find a way of tolerating WiFi.  But LiFi would make some sense, as long as there was an uplink too.

[Chunkers]

I'm just imagining myself being absorbed in an intense BF4 game and the wife walks in and turns off the light, lol.

C

[tickmike]

If my memory serves me correct (possibly not) but hasnt li-fi been brought up and discussed on these forums before.  Possibly over a year ago, so I dont think the concept is that new.  I seem to recall it had several downfalls and although it may be useful in some instances its not ideal.

http://forum.kitz.co.uk/index.php/topic,13115.msg247281.html#msg247281

 

[Black Sheep]

  @  Wombat ........ "The only downside? Someone needs to be developing the backhaul... Fibre to the lightbulb?"

[Weaver]

 

Please god let no one mention homeplugs now.