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There is a way to get broadband to the boonies.
Are you more than 50 miles from fiber?

If so, you may need more than one of these.

It is configurable for good reason.

Take a look at the table available at: http://www.afar.net/tutorials/...

The dB values should not be static, as the inclusion of a directional high gain antenna can make you need to adjust the dB value to match the antenna to prevent overrunning the max allowed radiation (EIRP).

Also, not every country has the same rules as the US, there are actually many countries on this planet, and they don't all use the same set of EM rules.

Perhaps you should read the laws surrounding this stuff, as you are completely wrong.

http://www.afar.net/tutorials/...

You are legally allowed to nearly double the EIRP with a directional antenna. You are allowed a Gain of up to 30 dbi with a drop of 8 dbm of transmit power for a total EIRP of 52.

http://www.afar.net/tutorials/...

How do you implement the rules listed there for antenna gain?

If your equipment is used in a fixed point-to-point link, there are two exceptions to the maximum EIRP rule above:

In the 5.8 GHz band the rule is less restrictive. The maximum EIRP allowed is 53 dBm (30 dBm plus 23 dBi of antenna gain).
In the 2.4 GHz band you can increase the antenna gain to get an EIRP above 36 dBm but for every 3dBi increase of antenna gain you must reduce the transmit power by 1 dBm. The table below shows the combinations of allowed transmit power / antenna gain and the resulting EIRP.

            Transmit Power
(dBm)
      Antenna Gain
(dBi)
EIRP
          (dBm)
30 6 36
29 9 38
28 12 40
27 15 42
26 18 44
25 21 46
24 24 48
23 27 50
22 30 52

I don't see any way for the wifi router to tell the gain of the antenna you attach to it and automatically drop the signal strength.

The responsibility for staying within these power limits falls on the operator (or, if professionally installed, on the installer).

So if that is the case, why is this firmware lockdown even on the table, even with locked down firmware, you are responsible for staying within the power limits.

Wifi distance is a relative term. With highly directional antennas, that distance can be miles, even without exceeding EIRP restrictions.

You can use up to 52dBm EIRP, but by FCC rules you can only do that w/ a 30dBi antenna. That's very directional, like the kind of stuff that's used for carefully aimed terrestrial microwave links. That's hardly suited for mobile. Cellular mobiles, as opposed to the base stations, generally use omni's, or at least very low gain. MIMO can buy you a little, but it's not magic. Admittedly 52dBm EIRP is an extreme (the tradeoffs are here), but you still have the same basic EIRP vs. directionality issue. The coffee can WiFi antennas are cute, but only useful for fixed point-to-point stuff.

And you're not restricted to Wifi: Any network technology which can carry IP (i.e. all of them) can be used.

What did you have in mind? And remember that the only reason WiFi transceivers are so cheap is because of the enormous production volume.

It doesn't take $2M to start a WISP. I would definitely look for the nearest wholesale bandwidth provider or datacenter and set up wireless backhauls to make damn sure you don't need T1s.

Bandwidth can cost $80/mo per megabit/sec, so set expectations accordingly.
If you're lucky, you can get it for $0.10/GB or less with burst to 100Mbit.

$20 per month per Mbit/sec throughput and metered use past the first 10GB may be sustainable.
Just get a 100Mbit backhaul, so it can handle a significant number of users.
Here's an example link with a range of up to 20 miles. The next part is to identify the most reliable point to multipoint setup for the last-mile setup.

You will want to consult the USGS topographical maps and do some math on the fresnel zone to make sure you can serve a customer before setting it up. This can also help you with antenna positioning.

Also, charge something like $0.30/GB overage - people wouldn't mind that and you'd get more profit the more they download. You should be able to support 1000 or more users on that, then you may be able to afford to contact Qwest for a dedicated fiber backhaul. After that, increase speeds and start getting fiber to your customers.

Three words for ya - Wireless Ethernet Bridge. Find your nearest datacenter and beg them to mount an antenna. This will go fifty miles.

WiMax is pretty well standardized from the perspective of protocols and modulations, but unlike WiFi which is developed for use in unlicensed bands, WiMax is primarily intended for use by network operators who will have licensed bands. (There will be some gear available for use in the 5.8GHz unlicensed band, but that is a small fraction of the market.

In North America, the main deployments are expected to be in the 2.5GHz "wireless cable" bands, which are mostly licensed to Sprint, the IFTS (educational TV bands) mostly licensed to Catholic Archdioceses but now authorized for subleasing) and a band around 3.5GHz. Various bands around 3.2, 3.5 and 3.6GHz is also where other parts of the world are expected to deploy these services.

If you are a large provider, like Sprint, you had better get field trials underway by now, or your licenses may be in danger of expiring. And you will be negotiating with a handful of equipment manufacturers for a wholesale deal on equipment working on your licensed frequencies.

If you are a small ISP, you will probably have to look to the unlicensed 5.8GHz, and talk to Alvarion. I have not looked much at who else has equipment for that band. Be aware that the higher frequencies do not travel as far as 2.4GHz, so you may in fact be better off with high-end WiFi kit built from the ground up for outdoor use.

If you are a user, you need to shop around for a service provider, and let them worry about the right equipment.

(I work for a small wireless equipment house that makes low-bandwidth wireless systems for very long range, especially targeted to underdeveloped areas of the world. http://www.afar.net/)