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Comment by GregoryPerry | Hacker News Reader

That's pretty much the intent and role of IPFS though. Based upon current saturation statistics for mobile telephone handsets (which has to be 95%+ for every person 15+ years old in the USA at least), you're only a few meters away from another handset that's likely GPS enabled. Why in the world do we need centralized mobile carrier infrastructure when mesh-based P2P comms are now possible over ISM band networks? An IPFS + 900MHz P2P mobile chipset addon + GPS-based geographical routed P2P communications transport for handsets (and rapid adoption of the same) is all it would take to eliminate the mobile carriers. This could be as simple as a BLE-enabled device or phone case...

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Mesh networks unfortunately scale really poorly [1]: O(1/sqrt(N)). You really need a fat backbone to turn the topology into something more like a hypercube.

[1] https://pdos.csail.mit.edu/papers/grid:mobicom01/paper.pdf

...for static ad hoc networks. GPS-based geographical routing would be a dynamic, constantly changing optimized mesh.

Type of routing doesn't make a difference for the above result. The main assumption is that node-pairs that want to communicate have random locations. That leads to O(N) pairs trying to go across O(sqrt(N)) links in the middle.

In practice who knows what kind of communication patterns you would get. Applications would probably evolve around the long distance limit if it existed, but it's hard to imagine not having backbone links. Most likely the meshes would stay relatively localized (and I believe there exist a number of regional wireless mesh networks out there serving real customers).

Unfortunately Shannon–Hartley theorem is very harsh on mesh networks.

900MHz in US is 902-928 MHz, 26 MHz wide channel. The usual SNR ratio range is 0-40 dB. This corresponds to total bandwith over entire band of 26 to 172 Mbit/sec -- depending on the range. Let's be generous and say 100 Mbit/sec.

You are not going to get any sort of beanforming from the mobile pocket-held device, so your collision domain is going to be everyone around you. Say you are in the park, and there are 24 people around you, and you are all routing packets for each other, so each packet is transmitted twice before leaving the collision domain. In this case, single person's ideal, best case bandwith is 2 Mbit/sec.

In practice, you are not going to get anywhere close to 100% efficiency, so I'd expect internet speeds significantly less that 1 Mbit/sec. This is going to be very painful.

Doesn't GPS and the wireless antenna use a decent amount of power and thus cut battery life quiet a bit if they're being used constantly?

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