3 ms·

I don't think this is a candidate to replace wifi. But if it's cheap and becomes ubiquitous (unlikely) it would make wifi a lot better. The advantage of the v

by mlyle 3y ago

I don't think this is a candidate to replace wifi. But if it's cheap and becomes ubiquitous (unlikely) it would make wifi a lot better. The advantage of the visible light approach is that it doesn't reach through walls. It's inherently very dense, and can provide users in its footprint nearly unlimited bandwidth. If it reaches only 50% of users in a classroom or office building, then those 50% of users will have very fast connectivity, and wifi will be twice as fast for everyone else.

ianburrell 3y ago
One place where it would work well is offices. Office buildings have drop ceilings that make it easier to mount devices on the ceiling. Then have one Lifi in each office or pretty dense in open plan offices. This could solve the problem of getting reliable speeds to devices without Ethernet, that are either hard to wire or don't want to plug in.
- cornholio 3y ago
  The speeds would be completely reliable until somebody starts walking around the office, disrupting the line of sight to the lightspot in the ceiling.
  - xoa 3y ago
    Like, sure it'd vary by office, but a lot of us are in spaces with pretty high ceilings and even a very tall person wouldn't be able to disrupt the view of most lights. I think the assumption here is LiFi, or other highly directional tight beam possibilities, would require significantly more density of WAPs. Maybe not every light replaced but a solid grid in most spaces, and then clients would be regularly connected to different ones and rapidly jumped between them as needed due to movement/obstruction (conceptually the same as Starlink for example which constantly connects, tracks, and rapidly jumps between sats which are LEO and thus constantly moving over the horizon). Part of the implementation standard would be handling all the packet shuffling for that, which will have to be enormously better then WiFi Roaming. Higher density is more costly too of course, but even so depending on the performance that might well still be cheaper/easier then fiber drops everywhere, plus it'd avoid some of the minor but sticky end user physical interface issues of fiber connections. Whether the value is there remains to be seen and will no doubt vary, but as others have said a lot of typical office plans (with drop ceilings, ceiling rails or other designs meant to enable more modular ceiling use) on the surface seem pretty amenable to such an approach. Ultimately all depends on what the actual implementations look like though, and at what cost.
  - mlyle 3y ago
    If you have quick enough failover to wifi-- who cares. I'll happily take 75% availability of dedicated 2gbps and less-congested wifi the other 25% of the time.
  - ianburrell 3y ago
    LiFi signal bounces off walls. It doesn’t need direct line of sight. Think a light bulb lighting a room. But it doesn’t go around corners and through walls like WiFi.
- fbdab103 3y ago
  Isn't this solved by POE? For an office building which already has extensive electrical/networking/plumbing needs, pulling one dedicated wire for a robust networking connection seems worth it.
- beenBoutIT 3y ago
  It will work well in a lot of places where lag is an issue. Should make lag-free wireless video game controllers and full-bandwith lag-free headphones a reality.
  - aifooh7Keew6xoo 3y ago
    at least until the shadow IT crew starts bringing in their LiFi lamp shade routers
- hulitu 3y ago
  Yeah, because everyone needs fluctuating light 8 hours a day. It is like seating do not destroy your health enough. /s
xoa 3y ago
Right, it's another possible candidate for true high bandwidth "wireless wires" for applications like uncompressed video, external PCIe, high speed data access etc. Wearable displays are the most obvious candidate, it'd be very useful to be able to have the bandwidth on tap to perfectly replace DisplayPort/HDMI/Thunderbolt for 8k+ video while in an office, along with access to office NAS/SAN and potentially seamless use of other peripherals like GPUs. That would mean a wearable display could potentially function as a true no-compromise monitor/system replacement, and then transparently downgrade to independent mode when leaving. As you and others say that could even be an extra security advantage, that while sure there'd absolutely be authentication, it'd be an interesting capability that only a given light cell in a given room/cubicle/area could access particular VLANs or the like at all. The range being short doesn't negate the benefit of no wire, nothing to snarl or snag or get forgotten about. And the backbone aspect seems to be coming along as well. 40/50/100G is becoming surprisingly affordable even now, and in another 3-5 years as this cooks I don't think it'd be a blocker even if it was high end for a solid period of time like most new tech is. There are other potential approaches but WiFi+LiFi hybrids could be neat. LiFi would also have the regulatory advantage of not needing to worry about typical licensing or bandwidth issues beyond basic emissions like anything with a power supply has, since those spectrums are of course fully public :). Although the industry could in principle muck the whole thing up with burdensome patents I suppose, but then again the basic principle are similar to fiber and free space optical transmission (including extremely high speed) has been done for ages so that might limit the scope of any potential claims to some degree.
- calamari4065 3y ago
  A hybrid with radio WiFi could be interesting. You could set up the usual ceiling light panels as a big fat downlink and use WiFi as an uplink. Would be pretty useful for public areas. I think an uplink with visible light might be too much to ask, but if we could just glue these two networks together, it becomes a lot more useful.
  - m463 3y ago
    There are lots of technologies where uplink and downlink are asymmetrical since downlink is used to consume data, and significantly more of it. I wish more technologies could do one-to-many broadcast. for example a live video stream that many were watching, or tv/movies/presentations where many people were listening to the same audio with headsets or earbuds.
mycall 3y ago
WiFi negotiates connections to determine the best frequency range to use. It could support line-of-sight visible light if it works for that particular setup, or fallback to 2.4/5Ghz when it doesn't.

by mlyle 3y ago

ianburrell 3y ago

One place where it would work well is offices. Office buildings have drop ceilings that make it easier to mount devices on the ceiling. Then have one Lifi in each office or pretty dense in open plan offices. This could solve the problem of getting reliable speeds to devices without Ethernet, that are either hard to wire or don't want to plug in.

cornholio 3y ago
The speeds would be completely reliable until somebody starts walking around the office, disrupting the line of sight to the lightspot in the ceiling.
- xoa 3y ago
  Like, sure it'd vary by office, but a lot of us are in spaces with pretty high ceilings and even a very tall person wouldn't be able to disrupt the view of most lights. I think the assumption here is LiFi, or other highly directional tight beam possibilities, would require significantly more density of WAPs. Maybe not every light replaced but a solid grid in most spaces, and then clients would be regularly connected to different ones and rapidly jumped between them as needed due to movement/obstruction (conceptually the same as Starlink for example which constantly connects, tracks, and rapidly jumps between sats which are LEO and thus constantly moving over the horizon). Part of the implementation standard would be handling all the packet shuffling for that, which will have to be enormously better then WiFi Roaming. Higher density is more costly too of course, but even so depending on the performance that might well still be cheaper/easier then fiber drops everywhere, plus it'd avoid some of the minor but sticky end user physical interface issues of fiber connections. Whether the value is there remains to be seen and will no doubt vary, but as others have said a lot of typical office plans (with drop ceilings, ceiling rails or other designs meant to enable more modular ceiling use) on the surface seem pretty amenable to such an approach. Ultimately all depends on what the actual implementations look like though, and at what cost.
- mlyle 3y ago
  If you have quick enough failover to wifi-- who cares. I'll happily take 75% availability of dedicated 2gbps and less-congested wifi the other 25% of the time.
- ianburrell 3y ago
  LiFi signal bounces off walls. It doesn’t need direct line of sight. Think a light bulb lighting a room. But it doesn’t go around corners and through walls like WiFi.
fbdab103 3y ago
Isn't this solved by POE? For an office building which already has extensive electrical/networking/plumbing needs, pulling one dedicated wire for a robust networking connection seems worth it.
beenBoutIT 3y ago
It will work well in a lot of places where lag is an issue. Should make lag-free wireless video game controllers and full-bandwith lag-free headphones a reality.
- aifooh7Keew6xoo 3y ago
  at least until the shadow IT crew starts bringing in their LiFi lamp shade routers
hulitu 3y ago
Yeah, because everyone needs fluctuating light 8 hours a day. It is like seating do not destroy your health enough. /s

xoa 3y ago

Right, it's another possible candidate for true high bandwidth "wireless wires" for applications like uncompressed video, external PCIe, high speed data access etc. Wearable displays are the most obvious candidate, it'd be very useful to be able to have the bandwidth on tap to perfectly replace DisplayPort/HDMI/Thunderbolt for 8k+ video while in an office, along with access to office NAS/SAN and potentially seamless use of other peripherals like GPUs. That would mean a wearable display could potentially function as a true no-compromise monitor/system replacement, and then transparently downgrade to independent mode when leaving. As you and others say that could even be an extra security advantage, that while sure there'd absolutely be authentication, it'd be an interesting capability that only a given light cell in a given room/cubicle/area could access particular VLANs or the like at all. The range being short doesn't negate the benefit of no wire, nothing to snarl or snag or get forgotten about. And the backbone aspect seems to be coming along as well. 40/50/100G is becoming surprisingly affordable even now, and in another 3-5 years as this cooks I don't think it'd be a blocker even if it was high end for a solid period of time like most new tech is. There are other potential approaches but WiFi+LiFi hybrids could be neat. LiFi would also have the regulatory advantage of not needing to worry about typical licensing or bandwidth issues beyond basic emissions like anything with a power supply has, since those spectrums are of course fully public :). Although the industry could in principle muck the whole thing up with burdensome patents I suppose, but then again the basic principle are similar to fiber and free space optical transmission (including extremely high speed) has been done for ages so that might limit the scope of any potential claims to some degree.

calamari4065 3y ago
A hybrid with radio WiFi could be interesting. You could set up the usual ceiling light panels as a big fat downlink and use WiFi as an uplink. Would be pretty useful for public areas. I think an uplink with visible light might be too much to ask, but if we could just glue these two networks together, it becomes a lot more useful.
- m463 3y ago
  There are lots of technologies where uplink and downlink are asymmetrical since downlink is used to consume data, and significantly more of it. I wish more technologies could do one-to-many broadcast. for example a live video stream that many were watching, or tv/movies/presentations where many people were listening to the same audio with headsets or earbuds.

mycall 3y ago

WiFi negotiates connections to determine the best frequency range to use. It could support line-of-sight visible light if it works for that particular setup, or fallback to 2.4/5Ghz when it doesn't.