Those were just prototypes made out of a garage.
Increase laser wattage = increased distance.
I’m sure carrier frequency matters too… some will carry better thru rain, smog etc.
Until we get scalar, it would need to be a HAM bridge, or a hacked connection, jacking into the current network outside of current onramps. Those connections could feed the parallel web, so only a few nodes have to take that risk.
This is only thru for line of sight connections. Only long wave transmissions (153 - 279 kHz) bend along the earth as @weirdnerd already signaled. Short wave ( 2-30 MHz) can bridge distances by reflection against the ionosphere.
Range is mainly not a problem for (strong) lasers, even a mirror placed on the moon by NASA was able to reflect a laser beam.
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FWIW: HF bounces off the ionosphere, not the Van Allen belt.
You can get temporary distance for FM by bouncing off clouds, a satellite, airborne objects, or if you dare, a meteor streak. (It takes some sophiscated tech to find those meteor streaks.)
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Hi Emily,
Interesting concept. Personally I think the focus should be on development of alternate technologies which don’t fit the current scientific (Telluric rather than Hertzian) and regulatory (spectrum, space licensing) framework.
I’m imagining an ELF network where the carrier is the earth itself, where code division spread spectrum techniques are used to multiplex (CDMA) traffic and where there are both publicly shared orthogonal codes for group communication and privately shared codes which effectively make the signals between two end points appear as noise. ELF/CDMA would be very low bit rate, but maybe its time to return to the early days of the internet … I’m thinking telnet and netscape navigator 
A few interesting thought provoking resources below:
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To be clear, I wasn’t advocating or discouraging anything. I was asking if it was legal.
pro tip: If you decide to break the law for the greater good… it’s good to know that your breaking the law. It can have a significant influence on OPSEC.
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Another pro tip: If you decide to break the law for the greater good … don’t discuss it and flag it on a public forum. 
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…unless you are doing it anonymously.
Not to be confused with ground telephony. Hearken back to WWI when a combat telephone had only one wire. The either end was plugged into the ground. That lasted until one side discovered they could listen in to the enemy’s telephone communications simply by plugging their own telephone receiver into nearby ground.
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yes, definitely interesting to go back to the early days of communication to see how these systems worked. A browse through old online patents reveals a fair few ground based approaches.
Interception is always a security consideration with any link, hence along with encryption methods, using a spread spectrum approach is ideal, for the reasons outlined below
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Even then I would say “no”. By flagging it publicly, albeit anonymously, you are allowing the authorities to take pre-emptive defensive action of some sort.
And let’s not kid ourselves as to exactly how anonymous a user really is. Are all users (or this particular user) doing everything right to strive for anonymity? The authorities have many tools up their sleeves to find you if they want to. So why give them a free kick?
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It takes a gov’t budget to transmit that kind of stuff. And a gov’t budget to intercept it!
(At least a rack of receivers to working in sync to de-multiplex, I would imagine.)
Here’s the interesting bit, it may be a lot less cost prohibitive and accessible than everyone thinks…
Everything you need to mod/demodulate spread spectrum signals (or many other modulation schemes for that matter) is readily available and open source (e.g. GNU software defined radio project). Being VLF/ELF you also don’t need expensive RF hardware to source/sink the waveforms, a standard computer sound card is more than capable from DC up to 8 kHz (which at least in my part of the world appears to be unregulated or at least not allocated in any spectrum planning by the communications authority, probably because the capability/feasibility to utilise this band has long been written off by those with other agendas). I’ll admit more research needs to be done to reduce the transmitter input power / physical size requirements of ELF/VLF, but it certainly could offer a free to the people alternative.
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The size of the antenna would still be an issue. Do you property rights for a large field?
Except for that pocket size version the Dept. of Energy made but would they sell you one commercially?
RE: ELF/VLF… since the waveform is so large, the bandwidth I believe is constrained. Have they solved this with a carrier wave on top of the ELF? Could we get at least dialup speeds out of it?
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Maybe a rate of 6 bits per second? Enough for text.
Like panning to a scene change in “Hunt For Red October”, little green text prints at the bottom of the screen with a twittering sound.
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From what I heard, submarines use very long wavelengths. Maybe that’s something you can learn from.
Hi Emily,
Yes, the constraint would be available bandwidth in the ELF band before hitting 0 Hz, not necessarily the length (size) of the wavelength. Actually the length of the wave is advantageous to propagation, meaning better suited to long distance transmission.
Using 8.3 kHz as an upper limit and 300 Hz as a lower limit (no allocations by ITU below 8.3 kHz presently) one could use the Nyquist formula (in the absence of noise considerations) to estimate a maximum theoretical bit rate. bps = 2 x B [bandwidth] x log2 M [number of symbols in modulation scheme].
2 x (8300-300) x log2 2 using basic On-Off Keying = 16 kbps
or
2 x (8300-300) x log2 256 using QAM256 = 128 kbps
where we lose the bit rate is when spread spectrum techniques are introduced for the benefits of jamming immunity, complexity of detection/decoding in the absence of knowing the spreading codes and multiple simultaneous access to the carrier (‘the earth’).
Typical CDMA/DSSS/UMTS spreading factors can range between 4 and 512, so say picking 64, we have to reduce our bit rate by this SF.
In the above modulation examples that would be 0.25 kbps or 2 kbps.
As Tracy points out this may be suitable for email communications ‘text’. Doing some fancy things in your protocol layer like multicasting etc, you might be able to support forum style ‘bulletin boards’ and static html/image sites - aka welcome back to the early internet
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Anyone with a ham radio license can build and experiment with new kinds of radio emissions in the allocated spectrum space. That could be everyone if everyone gets a ham radio license (easy enough). The allocated spectrum space is spread out generously accross all of the different types of radio bands. So ham radio would work for a mesh network as long as there is no encryption used (no “codes and ciphers” allowed by law). But a new mesh system could be developed and tested legally, as long as there is no encryption used and as long as everyone who transmits or relays signals has a ham radio license.
There are constraints. For several reasons, the microwave bands are required. Below 3 GHz (or likely higher), there just isn’t enough bandwidth available for everyone to share, even at low power and with a lot of switching. If you go below 30 MHz, the atmospheric propagation actually causes problems with local communications. You may be in New York talking with someone two blocks away until someone in Australia comes booming in and obliterates the conversation. Received signal strength and received locations are mostly random based on sunspot interactions with the ionosphere below 30 MHz and sometimes up to 60 Mhz or at times, even higher. The only choice is to use microwaves, lots of switching, and maybe even satellites. But not to despair, that can be done.
If enough people participate, there might be enough constantly moving public nodes out there to make low-power, de-centralized communications practical. A worthy goal at first might be text messaging. Occasional delays in minutes might be more tolerable in text messages than would be practical in two-way voice communications. Although ham radio codes and ciphers are prohibited, you only have to publish your protocols and keys to stay legal. You’re not responsible to assure that everyone is capable of listening-in as you use low power and move around. If a mesh network utilized a protocol that only forwards traffic through a logical shortest path of nodes at low power, it would be extremely difficult to spy on anyone unless you literally followed them around to see where they go from minute to minute, and have a way to know exactly where the mesh will route their next traffic through the system (impossible). So being a part of the mesh would provide all of the anonymity you need. Imagine that you are attempting to listen-in to someone else’s in-person conversation between two people. You’re in a crowded restaurant. The band is playing and there are various different conversations going on all around you. You’re trying to listen in to a conversation between two people two tables away. Every now and then, your targets move to another table. Eventually they disappear in to the crowd. How can you listen in to those people? You can’t. No one can unless they are invited and told where to go next. That’s not a code or cipher. And it can’t be hacked if done correctly. From what I know, a ham radio mesh network of this type should work.
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Build your own launcher and launch from a mobile sea-launch platform in international waters?