A typical computer is connected to the local network using either an Ethernet cable or WiFi. This project connects two computers together through lasers.
No mention of carrier pigeon? IPoAC has three RFCs!
I wouldn't be surprised if they were trying to remove them from the kernel since you can use a tun interface instead. They would be very good candidates for moving kernel functionality to userspace.
Back when 10M ethernet was popular, it was pretty easy to wire up something like this with the transceiver (AUI) port... wire the tx to a laser and the rx to a photodiode (or whatever), ???, profit.
There's lots of commercial equipment in this space too.
The AT tiny is not needed at all. You have a digital signal coming right out of the serial cable which can drive the laser using a buffer and a Schmitt trigger on the receiver.
Eliminating crosstalk is the tough part and requires some modulation to ensure the transceiver isn't accidentally listening to itself via reflections or picking up interference.
Look up point to point laser links. They have been around for quite some time.
I don't know why, but I would have expected higher speeds. Maybe my mind just assumes "lasers = fast". It would be interesting to know which factors make this setup unreliable at higher speeds.
I was vibe researching TUN/TAP devices a few days ago. Cool to see such cool projects using them. I was mostly thinking about making a VPN prototype through.
We know neolithic internet used free air lasers because we haven't found either optical fibre connectors or copper Ethernet in the trenches we dig at neolithic settlements.
I have always wanted to give this a try. I have this daft idea of implenting a system logically as an n-dimensional cube and physically on two facing surfaces (even and odd parity processor addresses) with laser connections between the processors. Perhaps it'll be one of my crazy project ideas that I can do in my retirement
None of this is remotely new or interesting. I was doing IP-over-laser-light at Ethernet speeds over kilometer distances using free-space optics thirty years ago, and even then it wasn't a new technology.
I remember trying to my own data transmission over lasers ages ago, back when I didn't really know about how to properly transfer data (PLLs, clock recovery, error correction, etc). It lost timing pretty quickly, but it could just about do a hello world
When I was about 10-12 for a school science fair I built a device called a "photophone" [1] - one of Bell's lesser known inventions.
Basically, a filament flashlight is modified so that a magnetic coil was placed in series. An audio source is then fed through a second coil -- I can't remember the exact details of how this worked. The audio source was one of those fisher price sing-along tape players that I also modified I think. The tape was Abba.
On the other end, a cheapo solar cell was hooked up to a small kit amplifier and then you could hear the audio on a pair of headphones.
This was in 2002 ish, so fibre optics was a thing, but it was basically sci-fi for a scrappy kid in southern Africa. My whole spiel was how this was the precursor to fibre optics, and how one day all communications will be done using light in stead of electrons.
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[ 5.8 ms ] story [ 57.7 ms ] threadNo mention of carrier pigeon? IPoAC has three RFCs!
It's shooting a laser through a fiber optic cable.
https://github.com/mikeakohn/small_projects/blob/main/ip_ove...
I .... wonder if they considered just using PPP/SLIP?
There's lots of commercial equipment in this space too.
Eliminating crosstalk is the tough part and requires some modulation to ensure the transceiver isn't accidentally listening to itself via reflections or picking up interference.
Look up point to point laser links. They have been around for quite some time.
That thing was awful.. lol.
The link was dead during
- Heavy rain
- Fog in the early morning
- While snowing for days
- Pigeons building a nest within the optics
1: https://x.company/projects/taara/
Basically, a filament flashlight is modified so that a magnetic coil was placed in series. An audio source is then fed through a second coil -- I can't remember the exact details of how this worked. The audio source was one of those fisher price sing-along tape players that I also modified I think. The tape was Abba.
On the other end, a cheapo solar cell was hooked up to a small kit amplifier and then you could hear the audio on a pair of headphones.
This was in 2002 ish, so fibre optics was a thing, but it was basically sci-fi for a scrappy kid in southern Africa. My whole spiel was how this was the precursor to fibre optics, and how one day all communications will be done using light in stead of electrons.
Fun times!
[1] - https://en.wikipedia.org/wiki/Photophone [2] - https://www.youtube.com/watch?v=SxlWrqioifg