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Preferably, fiber optics will be used. However, it is very difficult to have a good overview of possibilities, and fiber optics technology is apparently very expensive to implement.

You can ditch the fiber but keep the optics. Free Space Optics (FSO) has been around for a long time. Despite being somewhat obscure, it is a very mature technology with a lot of things going for it. It provides fiber level bandwidth without the cost of digging up the ground to lay down fiber. Rapid deployment and high mobility can save not only money but time as well. You didn't mention how far apart the residences are in the neighborhood, but unless you're rural and very spread out, FSO may perform satisfactorily with allowance for bad weather. Bad weather being fog and scintillation.

Fog is a problem if you're near the coast or a large body of water that can produce a lot of mist. A heavy mist can really hammer the signal by several dBs over long distances on the order of a mile/kilometer. Currently it is the largest obstacle faced by permament/semi-permanent FSO implementations. Atmospheric scintillation is the phenomenon that makes stars twinkle at night. It is caused by variations in atmospheric temperature that change the index of refraction an optical signal encounters as it zooms to its destination. This problem, however, is more or less solved by making the signal take parallel paths to the reciever.

you may be interested in the following companies among others.

tellaire

terabeam

fsona

airfiber

lightpointe

industry news and references:

http://www.freespaceoptics.org/
http://www.wcai .com/fsoalliance/

AirFiber

Commercial-wise, my "favorite" (I am not affiliated with them or anything - I just like the tech) company doing this is a company called AirFiber. What is most cool about the tech is that they have an "auto-alignment" system to compensate for any angular/distance changes in the laser. That would be cool unto itself, but what gives it geek cred (and is little known - though I remember reading an article about it either here or on some other site a few years ago) is that the mirror alignment system was originally designed and prototyped (perhaps even uses it today - dunno) using an automobile electric-mirror positioning system (basically a fancy pushbutton external mirror alignment).

Of course, any discussion about LaserComm or LEDComm wouldn't be complete without mentioning the homebrew Twibright Labs Ronja Project. There are also a few other such projects out there (none as advanced as Ronja, IMHO) - I have mentioned them in other comments on such articles here on /. - search for them if you care...

It I am not sure how this is article bestows very interesting or novel information. Granted, the article mentions the wavelengths used are "visible", and "red". My guess is that they are emitting somewhere between 600 and 800 nm (typical visibly range is from 400 nm (purpleish) to 700 nm (red) however this is not a strict cut off, and if bright enough, even above 830 nm is visiblish).

Most telecom takes place at about 1550 nm, well into the infrared, but this is primarily because the typical fiber has nice properties in this range (absorption and dispersion). Therefore I am not sure there is much fundamental difference between infrared light telecom and visible telecom. Indeed they use very similar laser material (GaAs-based or InP-based diodes), are modulated the same way, etc.

Possibly this is neat because it is free-space optical stuff. However this (as pointed out previously) is not new. There are companies that are in place as we speek. Maybe deregulation may be of interest, but if the light it kept at the same wavelength as in fiber, then there is no need for an electronic klugey transceiver (detect the light in the fiber at 1550nm and drive a laser to re-emit the same signal at 6xx nm). Instead, an add-drop filter could be slapped on to the end, pick off the right wavelength, and feed that to a fiber which could be collimated as the source. This collimated beam then could travel over kilometers with no trouble. An all optical solution has a much

just a thought

The fact is, 802.11x communication systems ARE REGULATED BY THE FCC. If they chose (or were ordered), they could easily deem the spectrum used by 802.11x to be off-limits to anyone! Sure, I have heard the comments like "but businesses have invested millions in 802.11 - they would howl" - perhaps they might. Or perhaps a transition would occur to make the larger companies happy, by providing some form of wireless that isn't available to the average consumer like 802.11x is - but still gives those communications companies a foothold in wireless comms, while making consumers happy, and also possibly providing an easy place for the feds to tap, while making community nets a thing of the past (think it impossible? Try to buy, as a consumer, your own TXRX system for a cell phone - good luck, if you can even afford it). Everyone (mostly) wins - except for the citizen, ne - consumer...

I have said many times that the government has this (unelected, unrepresented) power via the FCC to do this (think I am joking? Do a search on my past comments, if you don't believe me). In these same comments, I have presented a solution that very few have worked on (at least on the homebrew front), that could keep community networks alive, a solution the government (FCC) cannot regulate (but oh how they would try - and if they succeeded, well - then that is the cue for true revolution):

Laser/LEDComm

I daresay RONJA is probably the most advanced "homebrew" system out there (if anyone has links to more advanced stuff - such as on the order of homebrew sighting/retargeting systems like AirFiber's System - please post links!). Other links of interest:

http://www.alphalink.com.au/~derekw/upn tcvr.htm

http://www.hut.fi/Misc/Electronics/circu its/laserlink.html

http://www.geocities.com/Silic onValley/Lakes/7156/laser.htm

http://www.n1bug.ne t/tech/laser/laserfr.html

http://www.n1bug.net/te ch/laser/alc_wa6ejo.html

http://www.repairfaq.org /sam/lasersam.htm

http://www.qsl.net/w1vlf/techin fo/optical_transmitters.html

http://misty.com/peo ple/don/laserdon.html

So - these systems have problems (line of sight being the largest) - but all systems have problems. At least one company (AirFiber) is using similar tech to run a business for WAN layouts - so it should be possible for a homebrew solution to be worked out. Are we going to simply wait until 802.11x really gets "outlawed" before we do something? What kind of shit is that?

Oh - wait - this is /. - where apathy seems to almost be the rule when it comes to politics...

Also, speaking of the 622 Mbps optical links, it sounds like what AirFiber is using in their system described on this page.

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