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Comment Re:Folly (Score 1) 394

The thing is, we're at peak oil now, and we're going to be peak coal in only about 20 years, so the cost is going up anyway, we either build out now, or later; and you may have noticed we've been held hostage by gas suppliers for example.

Your figure for how many wind turbines is also completely deceptive. The point of wind turbines is that they can be sited on farm land, and don't take up any significant land area; you can farm underneath without problems. The wind we have in the UK is actually enough to power the whole of Europe.

Comment Re:The number of devices is not most relevant (Score 1) 346

No you route between a few *different* frequencies with basically no delay. You only need a few frequencies to avoid interference, just colour the space so no two bubbles of transmission volume are the same frequency. (Having a few different frequencies is how cell phones work for much the same reasons.)

You've also obviously not understood the point about contention ratios; hosts are only sending for a fraction of the time, they don't need full capacity all the time. In fact most of the time they don't need any.

So if I've got an 11 Mbit/s access point, I can give ~11Mbit/s access to (say) 5-50 users and they won't notice too much difference. Essentially ALL internet access is (in reality) a contended service. You can get uncontended, it's just much more expensive.

Comment Re:The number of devices is not most relevant (Score 1) 346

You don't need one per desk, you need one per n users, where n is the designed contention ratio.

So the total bandwidth winds out to be per volume, but you can design in how much bandwidth you want to support.

The thing about latency is that there's virtually no minimum, some routing techniques give 1 or just a few bits of delay at whatever speed you're using (say 16 bits at 100 Mbit/s, which is well under a microsecond per hop); you don't necessarily have to wait for receiving the whole packet before routing it on.

Comment Re:The number of devices is not most relevant (Score 1) 346

I don't necessarily agree about the latency thing, individual nodes can have access to two different frequencies and can be listening and transmitting at the same time, with very low delays indeed.

And the problem about having too many nodes trying to use the same internet access point, all you're saying is that you don't have enough access points. But then so what? No network, not even wired networks, can survive oversubscription of any one node.

Comment Re:The number of devices is not most relevant (Score 1) 346

Actually, it's counterintuitive. In the old days radios used to "shout" and then you can only get one sender on each frequency.

Modern kit adjusts the loudness (intensity) of the radio so that it just reaches the next node, and then they route it on.

Provided the environment is at least somewhat lossy, then there's no finite bandwidth- the more nodes you have, the more bandwidth you have, in proportion.

It's a bit like when people talk to each other in a classroom, there's lots of information exchanged, whereas they all have to shut up when the teacher talks to the whole class and there's far less exchanged in total (although it's hopefully more important). That's also pretty much how cell phones work.

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