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On one hand, I see where this could be helpful in certain scenarios like an office, where there is a consistent and planned layout specifically for the purpose of productivity. Or for military applications, where EMSEC is taken very seriously (to the point where Wi-Fi is generally not used at all in most classified facilities). Though I am also not convinced this would change the calculus much there in reality.

On the other hand, I don’t see the draws outweighing what seem to be clear setbacks. E.g. if I put my LiFi enabled phone in my pocket mid download, it will completely cease to work.

What is interesting is the idea of a much more comprehensively connected future. E.g. imagine a building either both Wi-Fi and LiFi enabled, with automatic switching between the two based on which is less congested and provides the best speeds. As our daily bandwidth footprint grows, I can see the benefit in having multiple spectra for information transmission.

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I’m not sure that this provides any benefit from an EMSEC perspective, as you’d basically be going from a position where you’re avoiding radios and even cables and similar things that aren’t TEMPEST shielded for fear of emissions leaking sensitive data, to a position where you’re broadcasting your sensitive data over the air, and a listening device simply needs to look at your lights somehow. I will agree that it’s easier to block light than radio, but I think that’s where the advantages end.

I think you have this backwards. You'd still encrypt your transmissions same as if you were using WiFi, so its a wash in terms of security. But it should be much harder to jam your receiver/transmitter, because its point-to-point.

> E.g. if I put my LiFi enabled phone in my pocket mid download, it will completely cease to work.

The light part, sure, but the regular radio wifi part will be fine; it'll be slower, but it won't go away. Ideally there's seamless transition between the networks, LiFi if you have your phone out and there's a sender in the receiver's signal, WiFi in other cases.

I think it'll work as well as moving from ethernet to wifi, or from wifi to cellular, which is, it doesn't really work seamlessly and it's quirky :(

Your mobile phone needs to move between cellular towers quite frequently when you are moving around. You don't notice this handoff because it is important to the functioning of the network.

If we decide that moving from Li-Fi to Wi-Fi is important, we can make it seamless.

Right, but I think it's not pretty in our carrier's side. Maybe some more abstraction over where exactly is the data flowing through is needed similar to what Wireguard does.

Moving between wifi access points is already completely seamless in a modern mesh wifi network.

Right, this is similar to hopping across cellular antennas, someone tries to keep it seamless for you while hopping within their controlled environment, but we still have challenges when your public IP address drastically changes (Wifi->Cellular on phones).

With more demand hopefully they will fix that and they'll have sub millisecond handoff or something.

This is mentioned in the article

> Of course, Li-Fi isn’t going to sweep away Wi-Fi and 5G alternatives (nor wired networks). Radio waves still have a distinct advantage with regard to transmission through the atmosphere at great distance, and though opaque objects. Instead, work must concentrate on using horses for courses – with Li-Fi advantages being harvested where possible.

>* if I put my LiFi enabled phone in my pocket mid download, it will completely cease to work.*

As per your EMSEC use-case, this is also a privacy benefit, as your pocket becomes a defacto faraday cage guaranteeing that your devices can only transmit information when you want them to.

In your pocket, or just turn around so your body is in between the source and your device? Maybe reflections get the job done, but that has to harm data rates, right? I am not an optical expert.

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